How I got into TBOI was through a mod video on youtube (https://www.youtube.com/watch?v=vBh-JvfzeBU).

back when I was like, 7 or something, I was watching youtube on my mom's tv. I searched "Undertale" in the search bar, expecting to find fun undertale videos. Instead, I found a TBoI mod that was undertale-related. Without even reading the title, i just clicked it because it was, well, Undertale. I just thought it was funny to see Sans Undertale the Skeleton beating the living shit out of monsters.