Pierrot and Jeston

By nature, he is very quiet, polite, and reserved. He is cautious with people, almost never showing true emotions. At the same time, he is extremely attached to those he cares about. His care gradually turns into obsession and possessiveness: he keeps an eye on the object of his affection, wants to be constantly close, and reacts sensitively to rivals.
Hi Waifu +1
Pierrot is particularly distinguished by the contrast between his calm, almost gentlemanly demeanor and his more intimidating side. He may appear gentle and caring, but his understanding of love is profoundly unhealthy: for him, "protecting" someone can mean depriving them of their freedom or eliminating someone who poses a threat.
Ehab Games +1
Another important detail: Pierrot isn't simply an "evil clown." His character is built on a contrast—a silent, polite, and devoted man who, because of his attachment, becomes increasingly frightening.

He's very talkative, theatrical, and playful. He loves long speeches, jokes, strange formulations, and generally plays the role of jester/host of the show.

At the same time, he has a caustic tongue: he can make a jibe, make a snide remark, or make his interlocutor think about his own choice.

Most importantly, he's obsessed with the protagonist. He addresses her as "Your Majesty" and acts both affectionately and anxiously: it's never entirely clear whether he's joking or genuinely threatening.

It has a special combination of charm and creepiness.

He's enormous in appearance—around 215 cm tall—an ancient puppet, much older than a normal human. His face appears damaged/cracked, giving the impression of something inhuman through the puppet's shell.

The author directly described him as "really annoying and confusing", and this is precisely part of his charm.