Vel'koz is a movie star
http://vignette4.wikia.nocookie.net/nagiasu/images/3/34/Nagi_no_asukara-01-chisaki-ena-fish_girl-worried-scared-fear-emotions.jpg/revision/latest?cb=20140330003732
Yeah he's been in many different movies, mainly adult films. In japan...... Notice 
Senpai.