Experimenting with a Partner I Don't Love

I'm a software engineer and usually pretty rational. So when my girlfriend suggested we try something new involving roleplay with her friend, I was skeptical but curious. We established everything was consensual and that it wouldn't change our relationship dynamic. It ended up being surprisingly enjoyable, intellectually stimulating even. But why did I feel more intrigued by this than anything else we've tried? Do people need love to feel real connection during these moments?