Can anyone please tell me why my Zebra Danio keeps burying himself?

Come play with me, I won’t tell anyone

Wanna try it? i won't tell anyone 😜

Come taste it, I won’t tell anyone 🤫😍

Come taste it, I won’t tell anyone 🤫😍

Can you come to my house every night, I won't tell anyone😋💦

Come on bro I swear I won’t tell anyone

Come here, I won't tell anyone that I made you my bitch

18yo, I have been so curious to try this, any guy down to get

I promise I won’t tell anyone. Just please come to my room

come get some of mommy's milk baby, it's okay i won't tell anyone

Take it, come on, just this once, I won't tell anyone. Are you