First of all, is it actually a name? I think I've seen it in a few name-ish instances, but I can't recall. Secondly, how do you pronounce it? I've been saying "YASS-oo" but I don't know if that's right. Here are some combos that quickly come to mind. They're mainly Greek because I believe (correct me if I'm wrong) that Yassou is a greek word/name/whatever it is.
Yassou
MatteoYassou
MatthiasYassou
PavlosYassou
ConstantineYassou
DmitriYassou
VirgilYassou
NikolasYassou
Theodore
Anybody have any other suggestions?