@MikhailA Момче is a boy, момиче is a girl (and they’re both an it, i.e. neutral gender).
My name’s Nikolay (hence my nickname), which comes from the Greek Νικόλαος (Nike + laos) and means something like “victor of the people” (it’s a bit more nuanced than that, but that’s the common translation). And I have it because both my grandfathers bore it (well, one was Nikola, but that’s the same name anyway).
Btw, Marin and Denis are pretty normal names here – I’ve known people with either of those names. Heck, I think there was even one Marin here in the Middle Ages (probably Catholic influence though).