BIOGRAPHY - part 2
Sersi returned to her extravagant lifestyle in New York and was throwing a lavish party at her apartment when it was gatecrashed by two members of the Avengers – Starfox and the Wasp. During the party, Sersi received a message through her mirror from Domo, requesting her presence back on Olympia, where all Eternals were required for the Uni-Mind ritual. Sersi refused to attend and instead used her power to transform the mirror into a regular painting. Unfortunately, Sersi's party received further gatecrashers, only these were an unwelcome surprise: the Eternal siblings known as the Delphan Brothers, who had been sent by Domo to forcibly bring Sersi back to Olympia. Although Sersi was aided by Starfox and the Wasp, the Delphan Brothers used a power-dampening restraint on Sersi and captured her. Fortunately, Starfox and the Wasp were able to follow the Delpha Brothers into the aircraft before it departed and teleported away.
Back on Olympia, Sersi lashed out at the Delphan Brothers by turning them into armadillos, that is until Ikaris requested she restore them. Anger turned to delight when Sersi learned that Starfox was an Eternal of Titan. Despite her earlier refusing to return to Olympia, Sersi was glad to be back home and stayed at Starfox's side as they joined the other Eternals to form the Uni-Mind, the process where all Eternals would become one. However, during the event, the villain known as Maelstrom appeared, intent on making the Uni-Mind (and therefore the power of all Eternals) his. Fortunately, the Uni-Mind was disrupted by the Avengers, who succeeded in preventing Maelstrom from obtaining the power of the Eternals. Afterwards, Sersi planned to return to New York with Starfox, both wanting to keep partying. [Avengers (1st series) #246-248]
Sersi soon paid a visit to Samuel Holden, who was lecturing a group of scientists about the Fourth Host of Celestials, which had recently determined that humanity was fit to live. Oddly, none of the scientists could remember what Holden was talking to them about. Sersi told Samuel that, while normally only the Eternals retain memories of the Celestials, for some reason the Celestials saw fit to leave the memories of their existence with him. Sersi wanted to spend more time with Holden and suggested that they go to Paris, but Holden reminded Sersi that she was due at Thena's coronation. Sersi did not want to attend but, despite her preference to go to Paris, she returned to Olympia for the coronation. [Eternals (2nd series) #1]
Sersi was sitting on the windowsill of one of her apartments when a man who was attempting suicide leapt from the building rooftop. Seemingly on a whim, Sersi used her powers to make him 
come to a stop mid-air outside her window. Sersi reminded him that suicide was illegal and told him that she wanted to know what led him to this decision. The man, whose name was Dave Chatterton, explained that he had no luck with women. Sersi snapped her fingers and Dave re-materialized in her apartment, where Sersi and Samuel Holden were preparing to attend a party. Sersi spoke to Dave about making changes in his life, like the Eternals did, by forging out their own path. Sersi used her control over molecules to change Dave's clothing into a suit, and had him accompany her and Samuel to one of her other apartments, where a party was underway. However, when Sersi noticed Dave did not appear to be having much fun, she used several illusions to snap him out of his depression. Unfortunately, this party turned out to be yet another interrupted by a crisis with the Eternals. The immortals had located a Deviant fleet and Ikaris had declared war against them. Sersi only briefly joined the battle, assisting Ikaris at a crucial moment. [Eternals (2nd series) #3-4]
Sersi was called to a quorum on Olympia and, as she had done so previously, brought her human companions with her. As such, both Samuel Holden and Dave Chatterton were present to bear witness to Ikaris accusing Thena of treason against the Eternals. However, Sersi did not bother herself with the politics of the Eternals, and quickly returned to Earth with her companions. At dinner with both Samuel and Dave, Sersi revealed that she found Dave and his eye-opening awe of the extravagant lifestyle into which she had brought him quite refreshing. However, in an attempt to offer Dave something even more than her lavish New York life, she transported him to Olympia, dropping him off with some of her fellow Eternals. She told them that Dave wanted to join them on a life of adventure, before quickly teleporting away, annoying some of her cousins for lumbering them with Dave. [Eternals (2nd series) #5-7]
Preparing for another lavish party at one of her apartments, Sersi was shocked to receive gatecrashers before the party had even begun – her fellow Eternal Thena and the Deviant Warlord Kro. The two, apparently, were on the run and needed somewhere to hide. Sersi was not amused but Thena pleaded with her for help, as they had uncovered something diabolical in the realm of the Deviants that could lead to the end of both of their races. Thena confessed to not always treating Sersi with kindness, and asked Sersi to help her in the name of love. Sersi boasted that she always knew Thena and Kro were in love, and agreed to let them hide out at her party – as it was a costume party. Samuel and Dave, whom Sersi snatched back from Olympia, were on hand to help.
While Sersi changed her costumes throughout the night (thanks to her mastery over molecules) that didn't stop her from being recognized by Warren Worthington III, who remembered seeing her at a party he attended as a child. Sersi joked that she wouldn't want him giving her age away, and also expressed disappointment that Captain America was unable to attend the party, even though several other Avengers did. Other Eternals attended the party too and, before long, Ikaris arrived, certain that Sersi was hiding Thena from him. Sersi tried to calm Ikaris but he wasn't having it. 
When the Deviants (along with their new ruler, Ghaur) showed up, Sersi took control of the situation, transforming all of her guests into Eternals so that the Deviants would not be able to find Thena and Kro. [Eternals (2nd series) #8]
Sersi was contacted by Ikaris, requesting she assist on a raid of the Deviant City. Initially, she refused to join the raiding party but, in the end, Sersi did arrive in time to join Ikaris and several other Eternals. One possible motive for her change of heart was that she discovered that Ikaris' human lover, Margo, was missing. Sersi used her control over molecules to transform herself, Ikaris and the other Eternals in the raiding party into Deviants, so that they could more easily move about the Deviant City, Lemuria. Once there, they split up, with Ikaris giving various orders to them all, save for Sersi, as he knew she would do what she wanted. Sersi soon noticed a female Deviant called Yrdisis being taken away by Deviant guards and, after causing a distraction with an illusion of an explosion, Sersi altered her molecules again to appear as Yrdisis. Then, when the guards were distracted, she proved herself a true hero by taking Yrdisis' place.
Sersi found herself before Lord Ghaur, who informed her that she was going to become a duplicate for the human Margo Damian – unaware that Margo had died in an attempt to transform her into a Deviant to strike at Ikaris. Sersi maintained composure when she was placed into Ghaur's transformation machine and, thanks to her molecular powers, she was able to assume Margo's appearance with ease. However, Sersi's ruse was discovered by Ghaur, whose monitors 
detected that the woman before him was neither Deviant nor human. He slapped a brain-mine on Sersi and put her under his control. Ghaur believed that he could use Sersi as a weapon to destroy his hated foe, Ikaris.
Ghaur placed a bracelet on Sersi, which forced her to assume the form of Margo Damian. She was then set about on the streets of Lemuria, where Ikaris found her and freed her from her shackles. Ikaris’ reunion with “Margo” was interrupted by the inexplicable arrival of Dave Chatterton. In fact, upon being left at Sersi's apartment, Dave had become frustrated and set out to find her. Eventually, he had learned from the Eternals at Olympia that Sersi had gone on a mission to Lemuria. By happenstance, the Eternals had learned of Margo’s death and Ghaur’s plans for Sersi, so they had sent Dave to find her. Her cover blown, “Margo” then struck out at Dave, blasting him with her eyebeams. Although Ikaris prevented further reprisals from Sersi, the damage was done and Dave was mortally wounded. When Dave revealed that the bracelet was controlling Sersi, Ikaris quickly broke it and she was restored to her true form. Unaware of what she had done while under the bracelet's control, Sersi rushed to Dave's side and, as her friend died, he told her that the Deviants had killed Margo – and that he loved her. A tearful Sersi did not want to hear Ikaris' warning about human lives, and quickly told him that Margo had been killed also. The two grief-stricken Eternals then set about finding Ghaur, who was in a chamber preparing for the next part of his wicked plan against the Eternals. Although Sersi, Ikaris and the other Eternals fought against the Deviants, they were unable to prevent Ghaur from transforming himself into a Celestial. Sersi took part in the battle against Ghaur the Celestial and, with the assistance of the Avengers, the Eternals were able to defeat their deadly foe. [Eternals (2nd series) #10-12]
Sersi was likely told by Ikaris what she did while under the control of Ghaur that led to the death of Dave. Possibly not wanting the same fate to befall the other human male in her life, Samuel Holden, Sersi apparently ended her association with him.