tomie. what the heck happened?

ok so me an the missus rented tomie. looked cool heard it was decent. watched the whole thing. it was pretty entertaining. then came the ending… What the hell happened? i thought i was paying pretty close attention but it just kinda lost me.
explain please…

I have not seen “Tomie,” but someone is trying to explain it here.

Well, he was this deaf, dumb, and blind boy . . .