
"An emperor without heirs"? That would mean the ML's older bro, the current emperor, wasn't the former emperor's son.

I am guessing after re-read it must be either a translation error or his children weren't official heirs for a while because in chapter 9 they indeed say "the late emperor had 5 sons and 1 daughter," all from different mothers (so, maybe the emperor didn't have an empress, and only concubines?) The ML is mentioned as being the emperor's "half-brother" in chapter 1 or 2, and in chapter 9 they say he's the youngest son and full sibling of the (late emperor's) only daughter (meaning, that he and she were the only siblings sharing both the same mother and father)

LMAO I'm currently in this for the comedy horror: it's even creepier now that he says even *he* thinks it's weird, after having exchanged less than 5 words with each other, and met only twice... But dude, I might've still been able to think it's just teen horniness gone wrong and talking... if you hadn't started saying crap like "You came... MY DESTINY..." (who writes your script lines??? Please FIRE them)

What's "better" than regular gaslighting? Cosmic supernatural gaslighting...
Supernatural's real, most probably, cause unless she's completely bonkers, and if he's really gaslighting her, I don't think there are any drugs that anyone can slip her to induce that kind of sight/touch mismatch (or, at least, there can't be anyone who can give her a drug to induce that specific kind of mismatch in her head, including the one where she can't see him in the mirror, while fabricating and/or accurately "predicting" all her other hallucinations...: slipping her a drug while taking note of all her "visions", and then hiring some fishman-costume guy to hang from out of their skyscraper building's windows, is a bit of an overkill for any regular yandere dude... and probably a bit too costly).
But it's still hilarious even with the gaslighting... I mean, lol, I know I shouldn't be laughing, but if he's doing even that "flower bouquet for a head" thing on purpose... LMAO, then he's an over powered, overly bored, alien Over Dork... Imagine what level of boredom you'd have to have, to start entertaining yourself by doing that, lmao. I'm almost sorry for him, he really doesn't know how else to kill some of his eternal tedium of a time, I suppose.

It's nice but yeah, like other comments have said: too little too much, too fast, too soon. Dude "meets" FL and is "inlove", love-bombing her enough to kill someone from diabetic coma... She doesn't know that they're having a one-sided "reunion" of sorts, since only the lovestruck ML is aware while she has no clue that she's already met his disguised self many, many times before, so... a bit jarring how he goes from not seeing her in four years, to following her even to the toilet, the minute they get "reunited".
Lol it's hard to take it seriously with these dialogue exchanges.
FL: "You startled me! Why did you sneak up on me without making any sound?!"
ML: "Well, I heard you calling, and teleported"
FL: "Sure... what are we having for dinner?" (...I think I LOVE this girl's personality)