yup the same bug happened to me,
when i kick buu's ass i retreat to the base
to heal my self and that cotton candy followed me in the base and pound me there!!!!
whats his problem that's my base???!!!!
well buu is killed by our tower and the game still continues i didn't kill him and the game goes on until we reached 200+ kills we got bored and then quit well this is not a major bug but i hope the later versions it is fixed.
the version is 7.7 H