Doctor to the Trantoul family, first. Closest friend of Leon's fiancee. When he left on the crusades, she asked Mathias to go with him as medic. He proved himself a great tactician and when they returned he and Leon had come to realize that there was more evil within France than outside of it. He stayed with Leon's company and they fought together, hunting down the vampire known as- Walter I think?

[ He pauses there for now. That's what Alucard asked for. The connection. Not how it fell apart. If he was feeling particularly obstinate he would have only told him that Mathias was doctor to Sara's family, but half-truths are only dragging this out. ]