If you were Taihei, how would you treat your imouto Umaru?
I don't know
Probably not very different from how I treat my others family members
That's no excuse for being a brat. I would buy her games and stuff only when she deserve it and like hell i would let her play games all the time. I would encourage her to make friends
When she's being a spoiled brat, I'd fuck her in the ass after stapling her hamster suit to the ground making her unable to move, then force her to shrink down into her other form while still impaled on my dick, and as she screams in pain I'd keep pounding and pulverizing her tiny hamster organs.
Then I'd put what remains of her into the trash where she belongs and go on a date with Ebina.
The answer is obvious. Buy her geimu, chippu and cola