apologies, I can’t speak from experience because I am a straight male with a preference for women in their 20s and I’ve never tried meth or any amphetamine for that matter. however, I suspect that the massive dopamine release triggered by methamphetamine would have opened up your brain to new ideas and facilitated some sort of sexual conditioning similar to that which leads to fetishes in childhood.
In a similar way, intense non-drug experiences can lead to the emergence of new sexual preferences. for example, up till the age of 12,, I was always super aroused and sexually excited by girls bare feet but I honestly couldn’t tell you where that fetish came from. that fetish is still with me today, but One day at school when I was about 12, or 13 years old changed my life, forever by introducing a new sexual fetish, that is the desire for girls to spit in my face and in my food. I was walking in the playground and was engrossed in the thought of a particular girl I really liked, when I was suddenly pulled back by a group of people warning me, that there was a massive puddle of spit in front of me. I quickly moved away and felt extreme revulsion as it was a boy who spat on the ground. for some weird reason, a thought then crossed my mind, about how I would’ve reacted if it was one of the girls that I liked, who had spat on the ground especially since I’ve heard of a few instances of girls spitting. at first, I thought to myself that I would’ve reacted in a similar way, perhaps less disgusted, but still spit is dirty and I wouldn’t want it on me. however, with my wandering ADHD mind, this thought kept coming up especially when I would masturbate and a few days later I woke up with a desire for girls to spit at me being a full blown fetish. I know drugs weren’t involved in this experience, but I believe methamphetamine might temporarily open up a window of brain plasticity in the reward system in a similar way that hormones may do in puberty.