Makima's fate in the manga is quite complex and involves a series of dramatic events. She faces powerful opponents and has her own agenda that leads to significant developments.
One common character paired with Vergil is Dante. Some fanfictions explore a romantic relationship between them, which often delves into the complex dynamic of their brotherly bond and how it could transform into something more. It's a very unique take on their relationship.
Well, Makima's death in the manga is the result of a series of events and confrontations. It's not straightforward and is tied to various character interactions and plot twists.
Nero is also a popular character to be paired with the reborn as Vergil. Given Nero's connection to Vergil in the original story, in fanfiction, their interactions can range from mentorship - where Vergil helps Nero master his powers, to more adversarial relationships if the reborn Vergil has different motives.