My theory is that, if the send off actually got through, his memories of Caius will dissapear, hence, the transparency. Caius said that that place was where all the memories were so I think he's disappearing because he is supposed to be a memory there. I think. Ahahahahah
"so for him to stand there and get upset about the fact his mother's death would be meaningless is stupid because again she would die anyway even if she didn't have koichi" i mean, erasing his existence and not existing in the first place are two different things, are they not? sure, if his existence is just erased, his mom will still die, but we don't know for sure if she could have lived longer if she didn't give birth to koichi in the first place. his mom will just remain dead because there has to be as little change as possible, not because it's her fate to die at that time even if it's for koichi or not. idk maybe i just misunderstood what you said. also, will caius not exist (or just disappear, whatever is happening to him) because he sent koichi back? i don't think it's fair to blame koichi for this as if he /stupidly and consciously/ decided to go back knowing that that would happen to caius
what i mean is,,, his mom was gonna die regardless yeah,,, if he went back she's still gonna be dead and if he stayed somewhere along the lines she was gonna die, maybe not directly from him ie childbirth but anything could have killed her, he said he wanted to make his mom proud to show he was living his best or something like that but yet he's being shackled by the fact that he can't accept she's going to die. i would hope he knows at some point everyone dies and yes while sad some deaths are meaningless so just because he can't accept that fact he decided to go back to earth, yes he might show his mother that he's made something of himself but he denied the feelings of love he had for caius and yes he could potentially get a new love but he could also have that nagging feeling that he did something either terrible or he lost someone he truly loved and he'll never be able to find someone like caius again unless caius has a reincarnation on earth which I highly doubt but it could be possible.
ohh i see i get what you mean now :))
okay okay okay so i respect his dumbass choice but here's what i have a problem with,,, one caius literally said his mom was gonna die regardless so even if he did stay his mom would have died anyway and when he goes back to earth guess what??? she still dead,,, two not only did we spend 37 freaking chapters with these two slowly falling in love with them but we were also rooting for him to stay with caius because again we genuinely loved caius. so for him to stand there and get upset about the fact his mother's death would be meaningless is stupid because again she would die anyway even if she didn't have koichi,,, so now after 37 chapters caius is most likely not going to exist anymore and we don't know if koichi will learn of this and face the repercussions for his dumbass decision,,, what a somber revelation this is