First Mami sends her pee into someone else, now she leaves an unexploded bomb underground. ESP is a truly terrifying power.
Jokes aside, I really do like how undisciplined she is with her abilities - I think it's way more realistic for a young person to mess around with powers instead of being ultra-serious about them. I wonder if Hosoda and the crew were thinking about Esper Mami when making "The Girl Who Leapt Through Time?"