My Senior Brother's Daily Splits

#What should I do if my senior brother is acting weird? Asking online, urgent!#

As the title says,

My senior brother

is the best senior brother in the world.

He started acting weird after he fell to the demonic path in my previous life.

He seems to have a split personality.

By day, he is still gentle and refined, a true gentleman as pure as jade.

By night, nothing about him is normal. He's a thoroughly tsundere, violent maniac with terrifying combat skills.

I feel like my position is in danger qaq

----Let's be serious----

Once upon a time, there was a junior apprentice brother whose senior brother fell to the demonic path. He accidentally killed his senior brother, regretted it, deleted his save file, and started over. His senior brother was left with side effects when he loaded his save.

Later, the junior apprentice brother fell for his eldest senior brother, but winning him over is clearly twice as hard...

Truly gentle and refined * truly violent, tsundere eldest senior brother, shou / truly (?) upright and honorable junior apprentice brother, gong

P.S. 1. The split personality will get better.

2. The characters will stay true to themselves, and there will be no role reversals or pairings broken up.

3. The author really isn't aloof, thank you.

4. Their relationship needs time to develop. They won't fall madly in love all at once, but this isn't a slow-burn novel.

5. HE, definitely HE. Don't doubt the author's ability to give it a happy ending.

Forcibly acting cute.

And then the author realized it was no use.