The bond between a Gensokyo resident and a Gensokyo Pokemon...And it have to be Yukari, of all people.
Gengar is a very wicked and sinister pokemon, you can't never tell if is just playing around or planning your death (according to the pokedex's entries). Doesn't that sounds familiar to you?
The bond between the Trainer holding a Key Stone and a Pokémon wielding a Mega Stone takes physical form...The process instigates a type of evolution inside the Pokémon.
