it started with bad apple remade in some robotic things (i dont know what they are). right after i watched that video, there was the bad apple pv, i watched it and was fascinated by the animation, and also the music. just after that, there was the video about history of bad apple, watched it, got interested more, and went to watch memories of phantasm, i stopped at like, episode 3 or 5, but it was the one with okuu.
i then forgot about touhou, until suddenly it appeared again (i would know exactly when it was if my history didn't break for some reason, but it was around late 2022) and i got back into it, and remain a fan of it until now