I used to be really into host clubs, but I eventually moved on because it was too painful and unfulfilling. I probably shouldn’t tell my boyfriend about that part of my past, right?

I think it may help to first ask yourself why you want to tell him about this. If it’s because you want to feel a little lighter by opening up about your past or want him to understand you, I feel it may be better not to tell him at this point. There’s nothing inherently wrong with having been caught up in the host scene, and I’m sure you had your reasons and were doing your best at the time. However, your current boyfriend isn’t responsible for carrying that past or the pain behind it. From his perspective, he may not know how to process what he’s told, which could leave him confused or anxious. I don’t think the past is something you have to talk about just because you regret it, or something you must share in order to be honest. What matters far more is how you live now and how you relate to people after having gone through it. If, in the future, you build a deep relationship of trust, and there’s a reason to bring it up—such as him asking or the context making it relevant—it may be okay to mention it matter-of-factly. But if you’d only be telling him to make yourself feel lighter, I don’t think you need to place that burden on him. The fact that you were able to move on from that life is already a huge step. Please cherish who you are now and the relationship you have now.

People who get hooked on host clubs are either stupid or emotionally unstable, so it’s better not to mention it. I’m not saying the hosts themselves are stupid.

If your boyfriend has been obsessed with a sex worker or hostess, or got hooked on a pushy person and spent a ton of money on them, you might actually have something in common. Other than that, if you’ve already moved on from papa-katsu (compensated dating in Japan), I don’t think you need to tell him. It’s great that you were able to move on. I once dated a woman who was addicted to hosts and was doing papa-katsu (compensated dating in Japan). She had completely lost sight of everything around her and seemed to be putting all her money into it. It got scary, so I ended things early, haha.

I think it depends on the relationship between you and your boyfriend.