In the beginning of BFDI, Bubble and Flower were already showing signs of being enemies. This interaction was short lived due to Flower being the first contestant eliminated and Bubble stayed in the competition all the way to the finale. In episode 21, Flower returns. This causes more tension and Leafy was brought into the conflict. Leafy and Bubble appear to be friends on and off, though their friendship seems stable as of Get in the Van.
In Take the Plunge: Part 2, after Flower calls Teardrop "stupid", Bubble warns her to be nice. This angers Flower, and asks Snowball to kill Bubble. Snowball refuses to, but then Blocky volunteers. Flower then cheers him on.
In Don't Pierce My Flesh, Flower's Speaker Box wishes Bubble (now Metal Ball) to be eliminated, and shoots a laser at Leafy. During the challenge, Leafy and Bubble run across Spongy as he falls into the magma. Flower also brags to the two (plus Firey) about how she'll win Dream Island and won't let any of them on before getting eaten by the volcano monster. Bubble and Leafy then stand together in the final moments of their lives before the magma wave covers and kills them. They then get recovered.
In Hurtful!, Flower forces Bubble to carry her to the top of a rock climbing wall. She says that if Bubble doesn't comply, Flower will pop her. At first Bubble refuses and gets popped, but then the second time Bubble does comply but only because if she doesn't, she will be popped. Bubble then throws Flower up but then Flower gets hit with a punching glove in mid-air. Leafy and Bubble get into a conflict at the end of the challenge. Leafy wants Bubble to win, but then Bubble tells Leafy to stop being so generous. Leafy gets mad, and then Flower gets into the conflict. She makes Leafy even more mad by saying that Bubble helped her. This leaves Bubble's friendship with Leafy destroyed thanks to Flower. Flower then kills Leafy and then says that their (Bubble and Flower) friendship has just begun and asks Bubble to let her win. Flower then goes into Bubble's arms to be thrown to victory. Bubble instead drops her in the magma, and then wins the challenge.
In Insectophobe's Nightmare 2, Flower demands an apology from Bubble. Bubble refuses to apologize, but then Leafy apologizes for her. Flower then accepts the apology from Leafy, leaving Bubble confused. Bubble starts questioning their relationship as friends, saying it isn't stable, thus making Leafy mad once more, and leading to Leafy having a conflict with Bubble again.
In Return of the Hang Glider, Leafy gave Bubble a cashew, which she was grateful for. Bubble also enraged Flower by saying she is tired of the ways she act around them, leading to Flower destroying all of the Recovery Centers and killing Bubble.