The concept of this MMO is cool, but it's also kinda extremely screwed up the longer you think about it. Several years is a long time to be in a certain body and identity. Then when it's over... what? Your character is gone for good? You can never again experience being in that world or body? The whole thing might be expensive, but I think the therapy you'd need afterwards might be even moreso.
While it's portrayed as a cute prank in-universe, what these two did to their brother -- effectively trap him in a body he didn't want for what will ultimately be several years -- is also horrifying the longer you dwell on it. There isn't even a point to it like Mihari Oyama did to get her big brother out of a rut. (and there's an unspoken implication in Onimai that Mahiro is cooperating and taking the drug in an ongoing fashion)
Am I overthinking all this? Yes. Yes I am. But in my defense, stories written in this fashion tend to put the setting before characters. Discussing the mechanics, systems, how everything works. So if the intent is to get me to think about those things then I'm going to notice what's disturbing about them. Whereas maybe I could put it on a mental backburner if I had quality characters or writing to distract me from thinking too much about this nightmare premise. (the gruesome in media res opening also casts a shadow over any future attempt to make this a chill slice-of-life fantasy story, so good job there as well author-san)
Speaking of writing, oof, that cliffhanger. Are we really doing this cliche already? i.e. "gender bent main character gets hit on by playboys, likely needs a male character or especially cool big sister figure to save her" . (while we totally do need to expose and call out the plague of pickup artists, this TSF/TG cliche usually just serves to drive in the sexist notion that becoming a woman is a debuff and unintentionally makes the pickup artist look powerful by comparison instead of the sad sacks they collectively are)
This could still be good, don't get me wrong. The art is very cute at least. But I definitely find it quite disturbing and I'm not sure that was the intent. Anyways, thank you for the TL! I didn't mean to sound ungrateful, I was given a lot to think about and I enjoyed doing so.