I know it's dumb, but IDGAF. It's my headcanon.
IDK if seadwellers all have the same size fins, but, in my mind, some have smaller ones than others.
#Homestuck
#Headcanon
#HomestuckHeadcanon
#Rainbow
THE WORDS:
For seadwellers, the bigger the fins, the more attractive you are. (Unless theyre like... 10 feet wide XD)
BTW, Selris has pretty large fins ;D

So people consider him SMEXY