Usually companies don't really do much when you use their stuff as long as you're not receiving profit and not claiming the images as your own, which it seems you're not gonna do XD
THOUGH don't underestimate companies, some just hate it when anything of theirs is used in any way. Mario and Sonic fangames are very popular and do a massively great job at being a great game, but Sega and Nintendo don't seem to take those games down as far as I know. Go forth and make whatever you wish!