Light it on fire, purify it from existence, and it'll take it easy forever.
If it passes yukkuri shiki then it wouldn't need to worry about oniisans, or smelly shit, or dissolving from its own urine and drool. In fact it doesn't need to eat anymore so it will not be fed. It can just go play with other yukkuris and go rub rub with alices.
Being angered by taunting is nothing to kill or mutilate it over. If it were pissing all over, or getting its drool on stuff, then we'd have a case, but this one is just reacting like a small child. Except this small child is also a memory-defective pastry who's probably the unborn stalk-baby that Anon took mercy on out of a group of home-invading trash, so the metaphor falls apart.
Ahh, just kill 'em all and let yukkuxanadu sort 'em out.