I'll teach you, little child. Yevgeny is his real name. Zhenya is a nickname. Eugene is the English name of Yevgeny. He is Russian. Now stop being confused
Evgeny/Yevgeny is his real given name, and Zhenya is the short form (like Christy for Christina) and also his nickname. Psikh is his underworld title/criminal alias
EVGENY!!!? Wait, Am I missing or forgotten something?! His name is ZHENYA what does EVGENY have to do with this?!