Major Story Arcs
Sofia is the daughter of Lorenzo Valenti, leader of one of the five main gangs in New York in the Shadow's universe, as portrayed in the Grendel vs the Shadow crossover. Sofia, a strikingly beautiful and intelligent woman who is also extremely ambitious, and feels that her father's management of the mob could be more expansive. She often consorts with one of Lorenzo's lieutenants, Johnny Palumbo, who looks out for her and her friend Frannie.
Lorenzo is very unhappy when Grendel (Hunter Rose) arrives in town and starts taking over all the organized crime in the city, starting with the Valentis. He is old-school and believes they are being disrespected. He had also planned on taking over all the mobs himself, so Grendel is ruining his plans. Meanwhile, Sofia starts to romance Rose. She first runs into him in his civilian identity, and finds him charmingly arrogant. However she also meets him as Grendel and is attracted to his powerful demeanor in that guise as well.
Johnny tells her that Frannie was beaten to death by her abusive boyfriend. She tries to trap the boyfriend and kill him, but is discovered. Luckily Grendel comes in and saves her and kills the boyfriend. She and Grendel finally embrace, and she actually gets him to remove his mask and reveal his identity, which he does for very few people. Indeed, Rose is conflicted, for he had sworn never to love again after Jocasta, but he finds himself fully falling for Sofia, somewhat against his better judgement.
Eventually Sofia manipulates Lorenzo into trying to kill Grendel and take over all the mobs himself, at which point she kills her father using Grendel's fork. However she then reveals that she has been secret lovers with Johnny the whole time, and they plan to frame Grendel for Lorenzo's death so that she and Johnny can take over the gang. Grendel is stunned, because he prides himself on manipulating others, and can't believe he was manipulated himself. However, women have always been his blind spot, as is eventually seen by his adopted daughter Stacy's betrayal.
He is considering whether to kill Sofia when he is shot in the back by Johnny, and the Shadow soon intervenes, so he leaves. Sofia and Johnny presumably remain the leaders of the Valenti gang.
It turns out that Johnny shares the same last name as Grendel's adopted daughter, Stacy Palumbo. It is possible that, at least in the Shadow universe and potentially also in the Grendel universe, Johnny and Sofia have children, one of which is either Barry Palumbo, Stacy's uncle, or Stacy Palumbo's parents. It is also possible, since she slept with Rose on multiple occasions, that any children she had would be Hunter's, not Johnny's, even if they were given Johnny's last name. Either way, this would make Sofia either the direct or indirect ancestors of Barry, Stacy, and Christine Spar, and thus an important progenitor of the Grendel legacy.