1. Toddness.
2. A Joking reference to heroin.
3. Hydrogen.
Person A: you are such an H!
Toddness: Why you always gotta be talkin' shiz?!?!?!
-or-
Marissy: Do you know where i can get some H?
-or-
K's Astronmy Professor: So a lot of Jupiter's core is made up of liquid H.
K OMG! If only Missi was here! Hahahhahahhahahahahahahaha