Flat

What ur GF is

Bruh, my girl is Flat

Velv

Velv stemming from velvet, a similar material to felt.
Felt can also be used to say I felt that, or I feel you, as in I understand and/or agree with what that person has said.
Therefore, "velv" would mean I understand and/or agree with what you have said.

John: Yo bro, imagine being to do like magic and shit like if i could put a spell on you and you'd like never stop floating that shit would be so cool.
Hiawatha: Velv

Leo

Has a world record for most chromosomes

"Man Leo is a total Jackass"
"Yeah, I heard he has like 64 chromosomes"