I don’t want to be the only cupioromantic here :(

I have no idea what the first two mean.

I can help
A demi-boy is someone who identifies as not quite a male or a female,demi-girls are a term and they are the same thing,demi-boys and dsmi-girls,identify as he/they for demi-boys,and she/they,for demi-girls
Cupioromantic means whoever identifies as cupioromantic might feel romantic attraction but doesn't feel romantic attraction

Okay. That makes sense now

Can you explain what cupioromantic means

Let me help you instead
Cupioromantic means whoever identifies as cupioromantic might feel romantic attraction,but doesn't feel romantic attraction

I'm guessing the last one was supposed to be sexual

Yeah,people shorten it to ace