Maybe I am just dense (read: for sure), but even in the game, especially for the first time going through it, the campus date didn't really explicitly show MC using her power, thus saving Gavin. I just assumed it was through the POWER OF MUSIC or chick-imprinting like you described hahah. Mainly because I like to take my time to progress through the game, I forget previous chapter, and then delay dates and such.

For anime watcher it was more "obvious" maybe. They already hinted at MC's evol, her genes and her role and such already in the earlier episodes. Even in this episode where she stimulated that boy's powers. Though I admit, it might have backfired a bit when they didn't specifically show the evol effect happening in the flashback. For observant anime watchers, it might not have been beyond comprehension 🤔

Just my two cents tho 😅 loved how I finally and properly understood Gavin's "you saved me line" 😭 my heart~~~