Grassy is very joyful and childish, he will usually get along with anyone as long as they don't bully or disrespect him
The two appear to be very good friends.
In "Getting Teardrop to Talk", when Basketball states that Loser is a great guy, Grassy agreed with her. Later on in the episode, Grassy tells Basketball that no one picked him to be on a team, Basketball picks him which makes him happy.
In "Lick Your Way to Freedom", when Grassy was having a difficult time saying the word "respected", Basketball helped him say it.
In "Enter the Exit", when Robot Flower tells her team that Remote sent their team a bomb, Grassy is sitting on Basketball's head.
In "Return of the Rocket Ship", when Basketball complains to Grassy about why Golf Ball distrusts her a lot lately and says that it's not fair, Grassy responds by saying, "I'm Grassy!" Grassy can later be seen sitting on Basketball's head when Robot Flower gets Golf Ball's rocket.
Status: Close friends
Grassy and Blocky became friends early in BFB starting with "Lick Your Way to Freedom", when Grassy tells Blocky that Golf Ball hasn't been treating him with respect. They are often seen near each other with Grassy sitting on Blocky's head.
In "Getting Teardrop to Talk", Grassy walks under a falling Blocky and has him land safely on his head.
In "Four Goes Too Far", while A Better Name Than That is celebrating Four's death, Grassy is seen floating above Blocky's head while Blocky is looking up at him; both of them have happy expressions on their faces.
In "Don't Dig Straight Down", Grassy agrees with Blocky when he calls Golf Ball stinky.
In "Questions Answered", when Donut communicates to A Better Name Than That via TV, he reveals that he can use his camera to transport his arms to the moon. Basketball exclaims that he should bring them back down to Earth with it, and Grassy agrees. Later during Cake at Stake, Grassy is the first to jump into Donut's hole after he says that they don't have to sit so far.
In "Return of the Rocket Ship", Grassy mistakes MMR for measles, mumps, and rubella and claims he loves them, Fanny then appears to say that she hates those, making Grassy frown.
In "Four Goes Too Far", he and the rest of his team multiply Four by zero.
In "Getting Teardrop to Talk", when Grassy said that their team will get up to lots of funny doings, Golf Ball says "We're not here to do funny things." In the same episode, Golf Ball insults Grassy, telling him that she thought he was an overgrown section of the lawn that the gardener forgot to mow. Later, Golf Ball praises him for saving Blocky's life and Grassy says that he's always useful.
In "Lick Your Way to Freedom", Grassy tells his team that he wants to be treated with respect, implying that Golf Ball was disrespecting him in the previous episode. When Four recovers Tennis Ball, like Grassy said, he continues to yell because Golf Ball is still dead.
In "Today's Very Special Episode", Grassy frowns when Golf Ball snatches a marker from him.
In "What Do You Think of Roleplay?", Golf Ball tells Grassy to prove that he isn't the impostor. In return Grassy says "I'm Grassy!", he becomes sad when Golf Balls how.
In "Don't Dig Straight Down", claims that he thinks Golf Ball is stinky when Blocky says she can't blame the grass for disliking her, confirming that their animosity is mutual.
Status: Minor enemies
In "Getting Teardrop to Talk", when Loser first appears, Grassy is seen smiling and shaking while everyone is cheering for him. When Basketball mentions that Loser is a great guy, Grassy says that he agrees.
In "Enter the Exit", Robot Flower reveals to the team that Remote sent them a bomb.
In "[[Lick Your Way to Freedom]"', Four says that he will only bring back one person. Grassy asks Four to bring Tennis Ball back, so Four does.
In "Questions Answered", Grassy sits on his head when the quiz show starts.
In "What Do You Think of Roleplay?", Puffball (in Basketball's body) calls Grassy "basic" when he slows down Golf Ball's investigation. This insult blows her cover, as Blocky points out that Basketball is friends with Grassy, and thus wouldn't insult him. Grassy himself doesn't seem to mind what she said about him.
Status: Enemies, on her side
In "Return of the Rocket Ship", Grassy unknowingly exposes that X's treasure are emeralds that are underground, along with their coordinates, to all of the contestants on the other teams.
A Better Name Than That
Just from looking at his teammates, Grassy happily assumes that they'll be sure to get off to a lot of funny doings.
In "Four Goes Too Far", Grassy and the rest of his team stand off against on the moon, waiting for the contest to end with the twinkle on either of their teams.