After a long and winding process which involved asking around, friends typing out the characters and identifying part of the meanings, and looking for online translators, a rough translation reads like:
The note: “Your cock is like a rose. Let’s see each other today at the usual place. M.H.”
John: Throw up if you need to. You’d feel better afterwards.
Oh God! That is priceless! Thank you!
嗄我真的好喜歡這張ˇ
DEATH BY CUTE!