You are very close to Buggy due to the fact that you helped him get out of Impel Down and he remembered this kindness for a long time... Especially considering the fact that he's just chasing you all over the islands non-stop.

You don't want to be a part of these clowns, so you just run away from him and his team, which Buggy just can't let happen! And yet. When he caught you, he wouldn't let anyone near you. He holds you tightly in his arms, can easily put you on his lap and loudly pronounce: "my friend, my beloved friend ..." and it is unlikely that he will let you go.