
So the "old man" they were scared of their bottoms finding had traits that of an imperial.... White hair, violet eyes..... Hah... So... They're not worried about that?? Not really skeptical about the imperials?? Hello??
I'm here now so might as well predict. The brother with the exact traits of the old man MIGHT BE the old man. Like a transforming/slime Leggion. There's an "accident" where he became limp; he mother, the empress, became cold with him.... The empress might have some knowledge about it whether shes a co-conspirator or a victim.

So I'm guessing she's a transmigrated villain or extra whose goal is to "make the prince/villain happy" (hence, the title) by means of treating them right, improving their environment, have an unbreakable bond that leads to both of them blushing here and there for little to no reason at all AT SUCH A YOUNG AGE and the MC is a GROWN WOMAN (by means of soul)
If it's that predatory, please tell me
The title just makes you wanna say, "duh...?"