Is this any way to treat your girlfriend's little sister?
Nope, Ame is a servant.
Yes, if bitches be crazy. She was going full babby mode whining about how the guy she liked didn't like her and wanted to have sex to prove she was attractive, MC was a man and put a stop to her dumb idea like one.
She's definitely his girlfriend, he's just a bit tsundere.
It's based off a 3-volume LN series of which the OVAs adapted the first and third volumes, so there's not really much they can do unless they went anime-original content.
Have you forgiven her yet?
Hm. If this image is true, I might have to get into this.
I can't believe you people actually like this MC. In the LNs he's the most useless piece of shit ever. They cut it from the anime but after being stalked by Ame his strategy for getting rid of her is to hire a bunch of other delinquents to rape her, and then he changes his mind just in time. He literally gets beaten up by his mum on a regular basis. And he spends half the LNs wandering around the city randomly trying to solve the mysteries, completely wasting all his time, and then finally gives up when he realises he's too dumb to achieve anything himself and asks Ame for help who promptly solves everything in seconds. And literally every fucking fight he gets beaten and is about to get killed before one of the girls jumps in and saves him.
Which is a shame because the 2nd LN is the best one imo. It's about someone kidnapping little 4-6 year old children, gouging out their eyes, and then returning them alive to live out the rest of their lives blind.
No one really cares, you watch this for Ame after all. Besides LN are trash and it's not unusual for an anime to actually improve on them significantly, as seems to be the case here. So you can safely ignore the shitty source material.