It's interesting people here are also mentioning they got completely hooked on something during mania, such as a favorite celebrity, etc. This has happened to me where I thought a particular singer and me had a special connection, and I would obsess for hours (and it wasn't during my teen years where it's more common to obsess over celebrities). Looking back, I see a pattern where it would turn into psychotic beliefs. During manias, I notice in general I tend get obsessed with something to the point where it's unhealthy and engage in strange behaviors as a result. Since others here are mentioning such similar experiences, now I realize this must be much more common in mania than I originally thought.