Popo's manga / #Time travel(1)

Vol2Ch3 extra It's confusing at times cuz of the time travel (also, I don't understand the logic of Tama's electrified body?? Like, only his hands and mouth shocks people but not the rest of his body???) but I think I got the jist of it. Basically our couple's relationship ended tragically when seme died in a car accident. Tama somehow is able to travel back in time to prevent this from happening. But he's unable to. Eventually, Kajiwara is also able to travel back in time to try to fix the same issue too but he doesn't have the same information as Tama does, mainly that he'll die. So these two guys (separately) keep going back in time to try to fix it. What they eventually figure out is that they need to work together to resolve it. And I thought that was it but it seems that kissing still sends him back in time. And the last chapter makes it even more confusing. So they travel back in time so much that they ended up in the past at different times so that Tama ends up a few years older than Kajiwara. Other than it being confusing, it's very funny and cute. Koyama is an adorable side character. Tho that one scene where he suddenly had like a very in-depth knowledge about how time travel works was out of character, especially as he is described as above average intelligence in school later on in the story.