@arashikitsu True; but this is a different matter entirely. He has absolute control, and enough confidence to get with strangers... so at least in the sex/harem department, he shouldn't be so wimpy.
Fearing monsters and fearing slaves you over power is different.
@FrostAether The problem is that this is actually an overly common trope in these series. If it was only this series, I'd have a laugh... but when it's done in way too many series I've read... it gets annoying...
It's more of a complain towards the trope itself rather than this specific series...