I think a lot of the popularity comes from just how gay the author made the two main male leads(Han Yoojin and Sung Hyunjae) and additionally it’s always mentioned along side Omniscient Reader’s Viewpoint and Trash of The Count’s Family as the self-sacrifice trio. But personally I think the author really nailed the character building aspect of the story (๑•ㅂ•)و✧ especially the mc’s character building and relationship with the other characters. The story itself can be a little random at times but I think it makes sense overall, it’s a fun read. Though just one warning, I wouldn’t recommend if you feel uncomfortable with authors using the story to clearly show their bias in terms of other countries. It’s not a big part of the story, but it’s there ┑( ̄Д  ̄)┍
I wouldn't say defending the world,yoojins a bit more selfish,he's alright as long as his loved ones are okay,be originally regressed to make sure his brother doesn't die again,then to get the body back.I feel like his motive does change somewhat to saving the world but not really, overall it's really funny and found family trope,mc doesn't become op either me remains F rank if you don't count boosters or his skill ranks which are non combat skills,it does get angsty down the line a bit,but it's really funny

Genuine question, why is this manhwa so popular? I always see it on featured but hav e ever clicked on an apisode, what makes it so good? What even is it about?