MC practically regresses for being the cause of his younger bro's death. there's obviously a lot more going on, like saving the world and shit, and him being responsible for that as a regressor.

The system side is divided into two faction, those who support honey (Han Yoojin nickname created by newcomer) in saving the world and the filial addict who want to destroy the world. Also the identity of some characters aren't that simple

There's an arc where Han Yoojin and his entire party got dragged into nightmare which is the world of Han Yoojin before regression. Before that there's also an arc where they got dragged into a previous world before it got destroyed, but in this arc everyone don't bring their real bodies except Yoojin. He died 3 times here

Luckily, Han Yoojin stops using the skills on humans and instead focuses it on beast animals.

HYJ is literally a complete 180 of who he was before. He's willing to say I love you to his brother, to rely on him, and even worries of what the public says about his brother. Not to mention the fact that he's legit searching for the transcendent that took his brother's corpse just so he can make the future 5 years Han Yoohyun and current five years in the past Han Yoohyun become one. He doesn't want to lose his brother, even if the current Han Yoohyun is no different from the one who died.

Crescent Moon. She's a bit loony, just like a lot of other characters

Sung Hyunjae's existence. There are 2 people the white bird predicted would be able to free him, MC and Taewon. Pre-regression, he and MC became sorta friends, but in the end he chose Taewon. Yeah that didn't work out.

Song Taewon's existence. Such a masochist, he's full of contradictions, but there's a reason for that! He's also another unstable guy, but he's doing what he thinks is right

Yoojin's f*cking title cancer. Seriously he's gonna die at this rate

The system admins. Not so innocent, not even the cute Newcomer

The White Bird that took hyh and disappeared