@Run thanks for the feedback :) I made a mistake in writing, I meant to specify 'visiting' as only kills. In short, this role basically turns someone into a bomb without taking away their action. It is like a one-time BG but the save lasts all game.
@TownTart I disagree. Roles like watcher would be there to confirm the planter. Although I don't think they should explode if there's any visit. It seems like a recipe for disaster because no town roles would do anything at night. Nothing of consequence would happen if they planted mafia, as well as it wouldn't help mafia without a role like the vig to shoot the planted, so in that case I'd say make it townsided. I really like the role idea!
I think it would only benefit the mafia, thus it should be mafia sided. What town wants to give a bomb vest to another townie or mafia, and then a townie like a watcher visits them. So it really does not help out town much. I like this role though! :)