In Japanese what they are talking about was dating with intention to proceed to marriage, so they're not only looking at personal and sexual compatibility but also when it comes to living together and growing as a family, which probably includes raising children. For that, how a person runs her household is very important. She's I think 2 years younger than Ayano so she's about 37 and the guy is probably (this being Japan) older than her so if they get married, they don't really have time to adjust and change. They better have their shit in order before going in or they're not going to survive as a couple. So it makes sense for him to cut his losses and start over. I mean, if all you're thinking about is having fun and then going about your way, how messy she is at her place doesn't matter, but it's a completely different story when you're hitting about 40 and thinking about building a family. Younger guys probably can't understand though.