Nyang Cat

Poptart is the femslash ship between Yang Xiao Long and Neon Katt from the RWBY fandom.

Canon
Canonnically, Neon and Yang only met two times : As the Vytal Festival Tournament and in the Volume 7, at Atlas.

At the Vytal Festival, Neon act as a brat, trying to make Yang angry even before the fight begins, attacking her on her anatomy (she says that Yang is "top-heavy", meaning she had a big breast). Thus, at the end of the fight, after Yang beat Flynt and Neon, she admitted that Yang was amazing "we should definitely party together sometime"... but it's not clear if she was talking about a real party or a fight... or both.

In Volume 7, team FNKI is finnally revealed whole, showing for the first time Kobalt and Ivori, because Oscar, Nora, Ren and Jaune trained against team FNKI. But team RWBY weren't there, so no interaction between Neon and Yang... at least until the 5th episode. Maybe we'll see more later on !

Fanon
This ship can appear as weird, because at first sight, Neon was kinda mean to Yang, but it can be some sort of ship dynamic, the bratty one and the strong one.