Roa

Though the Dead Apostles themselves merely see him as a normal Dead Apostle, the Church counts him among the 27 Dead Apostle Ancestors.
Known as the Infinite Reincarnator, he attempted to realize an immortality fundamentally different from that of the other Dead Apostles.
Originally he was a priest, but for the sake of surpassing his limits he had no choice but to become a vampire.
He tricked Arcueid, the strongest True Ancestor at the time, into drinking his blood, and immediately became a powerful Dead Apostle. Then, by unifying the factions of those Dead Apostle Ancestors who had already been sealed by the Church, he established his influence.
In response, Altrouge set out to put the newcomer Dead Apostle in his place, but by that time Roa was already powerful enough to defeat her instead.
As a result, the 27 Ancestors left Roa to his own devices. It wasn't until many years later that he was finally defeated by Arcueid and the Church working together.
After that, he reincarnated into new hosts a total of seventeen times, locked in a never-ending deathmatch with Arcueid.
He harbored deep emotions for Arcueid, who had stolen away his purity, but he was never able to realize that what he felt was love.
…Nevertheless, he was by no means a good person. In fact, you could say his amoral nature made him the hardest kind of person to deal with.
Similar to Nrvnqsr, the identity called “Roa” was fading even as he clung to eternity.
Though he did not actually become weaker with each successive reincarnation, none of his host bodies held the same potential as the very first Michael Roa Valdamjong.
At the very end he reincarnated into Ciel, whose body had potential close to his own, and Tohno Shiki, whose body would be his last.

Tsukihime Data Collection: Tsukihime Dictionary
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Full name, Michael Roa Valdamjong. A Dead Apostle. Though the Dead Apostles themselves merely see him as a normal Dead Apostle, the Church counts him among the 27 Dead Apostle Ancestors. Known as the Infinite Reincarnator, he attempted to realize an immortality fundamentally different from that of the other Dead Apostles. Originally he was a priest of the Church, but for the sake of surpassing his limits he had no choice but to become a vampire.
He tricked Arcueid, the strongest True Ancestor at the time, into drinking his blood, and immediately became a powerful Dead Apostle. Then, by unifying the factions of those Dead Apostle Ancestors who had already been sealed by the Church, he established his influence. In response, Altrouge set out to put the newcomer Dead Apostle in his place, but by that time Roa was already powerful enough to defeat her instead. Of course, it was only natural. Not only was Roa an excellent magus in his own right, but he was able to wield the power of the strongest True Ancestor, Arcueid, at the same time.
As a result, the 27 Ancestors left Roa to his own devices. It wasn't until many years later that he was finally defeated by Arcueid and the Church working together. After that, he reincarnated into new hosts a total of seventeen times, locked in a never-ending deathmatch with Arcueid.
Similar to Nrvnqsr, the identity called “Roa” was fading even as he clung to eternity.
Though the Roa that appears in Tsukihime has a rather brutal personality, that's because he's using Tohno SHIKI as his base. The original Roa was a calm intellectual.
…Well, he was still cruel and utterly selfish at heart.
He was obsessed by his thesis of eternity and was convinced he needed nothing else. However, the moment he laid eyes on Arcueid he was captivated, even though he should have seen her as nothing more than a tool. After that, Roa's plan spiraled totally out of control… though he himself never noticed.

Tsukihime Dokuhon Plus Period: Tsukihime Dictionary Revised
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