Merlin screaming in public things that are better dealt privately.
Ephtal denies it instead of dealing with the subject in private, and runs away.
That "actually she's my relative but I don't know her even if I mentioned I'm her relative and she's a rather important person" ad hoc.
Merlin correctly deduces he's the thunder emperor, but let's Ephtal brush it of with some insane theory about a mistress.
I know I'm not supposed to expect quality in isekai, but come the fuck on. Why is the idiot ball being passed hand by hand this way?