About Cosmo (SPOILERS)

Cosmo is a friendly laid-back neon monster who has a little brother named Blaine. Cosmo is 23 years old.

He is very loosely related to Luna. If you talk to him at some point in the beginning, he will talk about getting a DNA test. He will appear at some point later in gameplay saying "YOOOO Did you know that i am related to LUNA HERSELF?!?! She is very very distantly related but STILL!! I gotta tell Valara about this!!!"

Backstory

Cosmo explains his backstory at some point in the playthrough depending on your choices. Simply, he ran away with his little brother from his abusive parents when blaine was 5 and cosmo was 16. They ran super far away, and ended up being homeless. One time, a guy was about to kill them, but Valara, hearing all the noise, saved them. Valara offered them a place to live and they've been living at her place ever since then.

Other info

It's kind of obvious that Cosmo has a crush on Valara. In the pacifist ending if you have done the Blaine playdate and talked to cosmo at the bar, Valara and Cosmo may get married in the credits scene.

Cosmo helps out valara since she is blind (due to her entire face being crystallized before she arrived in Lun).

Squash once poisoned Valara's water supply, but cosmo noticed it before valara drank any water. He told Valara not to use the tap water until he is done fixing/purifying it.

Cosmo and Valara's favorite show is MTT(AKA Mettaton's show). Since Valara can't see what is going on due to being blind, Cosmo explains every bit of the events happening in the show, so she can enjoy it too.

Relations

Blaine (Brother)

Valara (Friends?)

Luna (Very distant relatives)

Squash (Cosmo absolutely DESPISES squash)

Mortimer (Mortimer babysits blaine)

Maya (¿¿¿)