Takeshi Yamamoto is the 14-year-old popular baseball star of Namimori Middle School. Despite his carefree and outgoing personality, he initially has no confidence in doing anything other than baseball, even attempting to commit suicide after sustaining major injury to his arm. After Tsuna reassures him, the two become close friends, and Reborn tries to recruit him into the Vongola Family. He hardly takes anything seriously, and is usually oblivious to what is truly happening around him, often tricked by Reborn into participating in Mafia-related events because he thinks that they are all just playing a game.