So you'd be fine with your little sister dating a girl that carries around cursed objects all the time? That sounds like the start of a shoujo ai/yuri isekai caused by a visit from truck-kun.
Honestly I can’t help but think Suzu the best. She makes the perfect Sister-in-law and has conquered the family when the other girls haven’t. The only way to officially become sisters is through becoming his wife!
Pudding, my new favorite replacement for the word [This indecency has been Pre-Post Censored for you, thank you and have a nice day]. And yup, i ship 'em ... the yuri ship sets sail.