I'm going to make fun of someone's proposal
Why would you make fun of someone's proposal?
He proposed in an unusual way
You are being insulting and rude by making fun of the way that someone proposes. Proposing is an individual thing and it is not your business how one person proposes to another.
I don't care they were both losers.
Have you ever come up with your own proposal? It might be harder than you think to be creative and have it work out. Can you even describe how he did it?