That urban legend about someone eating watermelon and the tree grow through their head (or variation of it). If I'm not mistaken there's also older version with Sakura tree growing on a man's head
Yamashiro, what do I do? I can't seem to remove it.Wait, hasn't it gotten bigger!?It's spreading its roots.Ehhh!?TreeEh?Eh?BrainThis is an extraordinarily precarious situation. We'll remove it via surgery.