Review Detail of DaoistvDKY87 in Returner's Odeyssey

Man where should I start? Let's start with the character "designs" Aside from the poster none of the characters are desribed what they are looking like. Like their looks, personality, traits, etc. The author might've glossed over it. Also I should warn that this is just polite critism for the author to improve later on in the future. While reading there are some bad grammar like the word "we're" when it's supposed to be "were" in the sense it's taking place. Then there's parts that don't make sense. So the MC ran to the bathroom to see himself in the mirror right? So he can see proof that he did indeed go back in time. While in the next line it says that Yui slammed the door open and stomped into his ROOM. Then in the next line the MC is talking like he is in his room. How? Isn't the MC in the bathroom looking at the mirror? After that, did he just go back into his room and closed the door? What would be the point in that? Plus it didn't state that either so idk what's going on in that part. Anyways this is my take on chapter 1. Take it as polite critism please. Thank you.