What's the difference between a twunk and an otter?

Posting my fitness body progression post, a person told me I've gone from skinny to ottermode. I've tried to google search it, it basically means slim, lean, and muscular. Isn't it the same as twunk though? Twink (slim) + Hunk (muscular)?

But somehow instinctively I feel like they're different.

By the way, here's how my body look, do you think I'm an otter?