When Bofur saw Bilbo clinging onto the edge of the stone ledge, his heart stopped, and when Thorin rescued him, Bofur couldn't help that bolt of jealousy that struck his heart. Even though he would never admit it, the little hobbit had grown very dear to him and the sight of one of his smiles set his heart pounding.
When they find the cave and Bofur is put on first watch, he's glad, because he can watch his hobbit from a distance under the guise of making sure the halfling was alright after his tumble.
When Bilbo tries to leave, Bofur's heart drops into his boots, because he doesn't want the hobbit to leave. He doesn't want to lose his Bilbo and so he tries to stall the eventual loss, for dwarves only love once and Bofur knows that if the hobbit leaves now, he'll never find another love again.
When Bilbo's anger gets the best of him and he near shouts about how the dwarves do not have a home, that they're built for a life of travel, Bofur thinks his heart will break, but he smiles, it's a sad soft smile that darkens his eyes and hurts his soul and he tells him
"I wish ye all the luck in the world laddie, I truly do"
Because he does, Bofur has never been one to hold a grudge, and so he prepares for the pain that watching the hobbit leave will bring, what he doesn't expect however is for a soft, small body to collide with him and for lips to descend onto his.
It takes the dwarf a moment to register the situation, but when he does, his heart soars and he's kissing back, just as enthusiastically, tongue tracing the seam of the other man's lips and grinning when he's granted entrance and when Bilbo moans against his mouth, Bofur is sorely tempted to bend his hobbit over and fuck him until he's screaming his name. He doesn't, of course, but the thought is definitely there, and he has to try and control the growing arousal he feels.
When the need for air becomes too great, they break apart and Bilbo rests his forehead against the soft material of Bofur's hat and he smiles.
The hobbit is about to speak when the floor beneath them opens up, and the company fall through the earth and as he and Bofur are separated both men think;
"If I die, at least I got to kiss him"