Now, here are some headcanons for the Spooky Kids themselves (and Lila, too).
1. Skid and Pump are huge fans of Boyfriend and look up to him. Seeing as how he was the first person they could test their songs out against, he doesn't mind them being fanatics. They also try to recite BF's songs. While they're not the best at it, they're slowly getting better.
2. Skid and Pump are very good at finding costumes for people and they understand if some people don't want to dress up on the Spooky Month. Skid's mom, Lila, helps out with making costumes and fixing them.
3. Skid and Pump wrote their respective songs from Week 2. Skid wrote "South" while Pump was in charge of "Spookeez".
4. Much to Daddy Dearest's horror, nothing he does actually scares the kids (even despite everything he's done, at that). When Skid and Pump managed to sneak into his mansion in Week 2, he gave up trying to scare them and doesn't care anymore, because he can't believe how two small children could be so fearless.
5. Unlike most of Boyfriend's other opponents, Skid and Pump were more focused on having fun battling Boyfriend rather than being too competitive or trying to kill him, even though they were manipulated by the Lemon Monster during Week 2.
6. Pico occasionally looks after the kids, even acting as a mentor to them. However, he's pretty aware that he could spill the beans regarding his job and past. Thankfully, Skid and Pump do see the best in him.
7. Since Skid and Pump are the youngest of the original FNF cast, they don't really take anything seriously (much like Boyfriend, of course). Girlfriend, however, would like it if they came with her and Boyfriend on adventures more.
8. Lila is friends with Girlfriend's parents. Lila knows that her son and his friend hang out with Pico occasionally, but considering the two kids have survived countless monsters, she's fully trustworthy of Pico. She also asks Girlfriend to babysit the kids at times.
9. Skid and Pump tried out "Lover's Delight" (aka Hating Simulator) while Girlfriend was looking after them one time. Needless to say, they found Senpai to be yet another new friend for them.
10. Pump is self-conscious about himself, while Skid is much more outgoing. Pump really feels safe whenever he's around his best friend.
11. Skid and Pump are slowly absorbing some sort of "spooky" powers within them. They might become monsters in the future, albeit friendly ones, but nobody has really picked up on this yet.
12. Skid and Pump are able to make anyone do the Spooky Dance.
13. As they do with other monstrosities, Skid and Pump have befriended the Lemon Monster.
14. Skid doesn't know who his actual father is, but he's fine with the Lemon Monster and Pico being some major role models he's found.
15. Pump is bilingual. He learned English in school, and his mother tongue is Spanish since he and his family moved to the United States from Mexico. That kind of explains why he has that funny accent. However, he doesn't speak Spanish quite often because Skid can't understand him, so he resorts to using English instead.
The reason Pump likes wearing his costume isn't just because he's a fan of Halloween and spooky stuff, but because he's a bit self-conscious of how he looks, and the big pumpkin mask hides his face.
16. Pump is from a poor family. They love him, but sometimes they can't afford a lot of necessities, which is why he's hanging out with Skid and Lila.
17. Pump invented the Spooky Dance while trying to imitate a mantis.
18. Pump has an inhuman level of curiosity. He wants to do and try and see everything just for the sake of "what would happen if this happened?".
19. Pump is described by Lila as "precocious". She believes he may have high-functioning autism or something similar, but he's very happy and healthy, so she doesn't let that concern her.
20. The blue in Pump's eyes contains hypnosis power, which he discovered after staring at a stray cat too long- it started doing the Spooky Dance because that's what was on his mind.
21. In Week 2, Pump swapped his tooth-print mask for a more flexible one that he could sing in, which he enjoys just as much as his normal Spooky Month one.
22. Pump met Pico while out on the street looking for Skid. They're on good terms, seeing each other like brothers, but he doesn't know anything about Pico being a hitman.
23. Girlfriend is very kind and motherly to Skid and Pump, but she doesn't know what Spooky Month is, so Pump's opinion of her is a bit mixed.
24. Pump's favorite food is cheesecake.
25. Pump's favorite video game is Spooky's Jumpscare Mansion.
26. Pump wishes he could be better friends with Roy and Ross. He's secret friends with Robert, but neither of them have told anyone else.
27. Skid moved around a lot when he was younger, but finally got to stay in one spot when he met Pump, and that's where he lives now.
28. Skid and Pump met one year prior to the first Spooky Month video, during Skid's first Halloween in his new home.
29. Skid has much more of an affinity for the spooky than Pump does, and wears his skeleton costume a lot because he wants to meet spooky things and become one of them.
30. Skid is trying to learn Spanish so he can make it easier for Pump to talk to him, and the longest sentence he knows is "¡Eres una cabeza de calabaza naranja!" (which, if you don't know, means "You are an orange pumpkin head!")
31. Skid wants to have the same haircut that Lila does, so he's trying to grow out the bowl cut he has now.
32. Skid doesn't know who his father is, which is why he's taken such a liking to the Lemon Monster. He's nice, big, and spooky- everything he wants in a role model.
33. Skid has a distaste towards Ross, who is easily the biggest threat between the Hatzgang. He knows Roy hates him, but he isn't sure why.
34. Skid loves his mom, and she loves him. They have a very strong relationship and he works hard to keep her from feeling down.
35. Skid loves Girlfriend, because of how sweet and spooky she is. They've made very good friends.
36. Skid's favorite food is Twix bars.
37. Skid's favorite video game is Luigi's Mansion.