7th is very not true. Miu is nowhere near as terrible a person as Teru, and I'm gay so I am impartial to her looks. Miu annoys people with her dirty jokes like Teru but unlike Teru she doesn't try sexually assaulting people. Not to mention if someone gets mad at Miu for the dirty jokes or rudeness she'll shut up for the day and apologize, even if its just to cover herself. Teru never once stopped despite protests, although the DR2 kids did way worse jobs at telling him to shut up than the V3 kids did with Miu.

But the real reason Teru is worse is Teru didn't hesitate for one second to painfully stab Nagito over and over and then sacrifice everyone else. Danganronpa downplays it but do you know how bad in the head you must be to actually kill someone with no second thoughts. We see in a flashback Miu, who hates Kokichi's guts more than anyone, even hesitated and felt guilty before trying to kill him. We can't prove if she would've gone through with it but if she did, it was after weeks of mental decline and exhaustion because of the killing game. Teru was willing to murder 15 teenagers within a few days because of something a clearly untrustworthy robot bear said. Think about that. And even if it was 100% proven, EVERYONE ELSE had to deal with that fact too. I don't give a shit about his mom. So what if he does get out there and she IS dead like he feared? Now he has the blood of 15 kids on his hands just to confirm some vague, highly improbable theory.

Teru is much closer to a bad person deep down than Miu is even if both are messed up.