The depth of Chris' delusion is difficult to get a handle on but here's what I think is going on
There's the pony chris (different from regular comic chris) who travels through a portal to the humanoid-pony world and becomes a humanoid-pony.
Then she meets her counterpart in that world and her counterpart's girlfriend.
Then she travels back home (becoming a normal pony) and meets her counterpart's girlfriend's counterpart.
Oh and apparently Sonichu knows her
Can someone just put a bullet in him?