I'm looking for a manga with a badass child. Not in a pairing with an adult and not the magical girl kind.

I would prefer it if he is silent and seems emotionless but cares alot about others. But can't get to attached because of some reasons.

Do you have anything in mind that's just slightly similiar to my description?

I appreciate anything

The forensic concubine or the forensic princess☆
Presidents priceless wife☆
My sweetest you☆
Prince's priceless baby☆
Honey dont run away agian☆
Doctor and daughter new
Hot mother☆
Like husband like son
Arrogent ceo: wife hunter☆
Free me now cold boss
Trampeled by the president ~
Deserted woman
My badass daddy ceo
Take your mommy home☆
Hi wolf captain☆
Contract of a fellingless ceo
Elaine's secret
Inescapable runaway love
Love you beyond my thought~☆
The hostage the lover~☆
Vampire Adonis
An exorbitant wife~☆
Indulged by ice president or spare me iceberg prince~☆
Be the kings daughter someday or I became the kings daughter one day all kids
Holy chef crazy empress
Counter attack of a pregnant actress☆
One night evil
~for kids appearing part way through
☆ for preferred ones

Dumb I read all this but I gave you all I know doing the quarenteen we need to stick togther far apart and if I help a bit I'm glad and giving book or this case manga recommendations I've always enjoyed it

Yakusoku no Neverland? Maybe...

Kiri<3FansClub<3MEOWS=^•^=nyah!!

The closest thing to your request I can think of is Hiraheishi wa Kako o Yumemiru.
The mc got back in time to when he was a child. He doesn't really give that "troubled" or "distant" vibe you're looking for, but he does have that "dark" theme about him.

There is also a webtoon called "The Beginning After The End" that kinda fits. (can't find it on mangaupdates)
The mc is a reincarnated person and he does give off a "distant" vibe at times, but gets along well with everyone for the most part. The mc here is pretty op.

Lastly, there's Mushoku Tensei, where the mc is also reincarnated, but he doesn't start off as a badass and in general doesn't give off a "dark", "troubled" or "distant" vibe. This fits the least to your request out of the 3 in my opinion, but it is very good, so give it a shot.

Also, keep in mind that all 3 of them are in a fantasy setting and in all 3 the mc can use some type of magic. Don't know if that's a problem for you, but just mentioning it to make sure.

Be careful of your thoughts, for they will become words.

Be careful of your words, for they will become actions.

Be careful of your actions, for they will become habits.

Be careful of your habits, for they will become character.

Be careful of your character, for it will become your destiny.