
It's probably the brother's command to find him...since puberty is hitting him they needed to teach him to control his body,It's not like the train is the only time he got jumped on, it's just the worst at the moment cuz peak puberty, I'll say it's the first time the seme saw him since he left the mansion ....and it is about the same time big bro withdraw from college abroad and went to find another heir since he can't be anymore

*they needed new heir so they went to find him since big bro withdraw from college abroad that is needed to make him the heir
*seme got tasked by the big bro to take care of him
*didn't plan to go more than the handjob
*didn't plan for it to escalate to intercourse but apparently it did cuz of uke's pheromone
*uke initiated the sex when he found out he's the same guy in his dreams
*Seme is holding back the whole time only wanting to protect the uke even at the last part when bringing him home to his mom he's willing to let him go trying not to be selfish with his desire until uke confessed
*this is complete fantasy and the pheromone kagami blood part strays it away to real life so we can't compare this to irl where a buttler is needed to keep sexual urge in check to keep people away from pouncing on you, seme's only doing his job and duties the whole time till it escalated to that

I totally understand that this is a comic, but the comic was written with a bunch of plot holes.
The older adult brother decided he did not want to be the heir so he had his butler go find the little brother who was in high school.
I was confused because the author could've easily just written in that the uke was 17-18, which still would not have been okay, but it would have lessened the charges lmao...jk but not really funny. The author intentionally left the age ambiguous; or maybe it's a translation error- excuse me if it is.
I get that this is hentai, but the mangaka intentionally wrote the characters "falling in love" and with that plot they also wrote it in such a way that the butler had more room to deceive the uke.
The seme lied when he said he contacted the uke's mom. The older brother didn't explain the whole Kagami blood thing properly(his only explanation was him having sex in front of uke). Also the seme intentionally left details out of his explanation when he had clear instructions from the older brother to teach him how to control his pheromones.
The seme knew of the immediate way for the uke learn how to control his pheromones but chose to put his hands on the uke even though he could keep his composure while the uke himself was struggling with his own body.
If it was just about an heir the butler would not have done the whole suck him off thing when he could control himself-nothing was stopping him from getting another butler to help with the task he was ordered to do; if it was too much. He just used it as an excuse to stay with the kid he had fallen in love with.
To me this is bad story telling on the author's part. Plus two men can't make an heir this is a rich family with enough resources to drop a bag and take away someone's debt.
That older brother just shirked his responsibilities onto a child/child adjacent?
the age thing is throwing me off....so he started liking him when they were both kids fine ...sure. knew exactly where he was when he was molested on the train....means he's been watching and lusting after him while he was an adult and dude is a teenager I'm guessing??? bc either he put an adult in high school to test his manipulative pheromones on high schoolers or this adult whose been after that booty has been putting his hands on a kid