I am pleased to meet you, Haruhiko! Welcome to the Island! I understand you may be a little confused... but there is no way for the people here to return to their homes, so all you can do is enjoy your stay here, train your Pokémon and meet new friends!

Can I ask... what is inside that building? It looks like... an ancient castle, except it also looks like a sort of... greenhouse, perhaps? What is it?

[He points to the castle curiously.]