[5] In his third year, Arita appeared four times for Kokushikan and he scored his first goal for the team in a 3–3 draw with Komazawa University, after only coming on as a substitute in the 85th minute.
[6] In his fourth and final year, Arita played a much bigger role for the university and scored 10 goals in 16 games in Kanto Division 1.
[8] He also made his first appearances in the Japan Inter College Tournament, playing three games before being knocked out at the quarter-final stage.
[9] In December 2021, it was announced that Arita would be signing for newly promoted J3 League team Iwaki FC for the 2022 season.
[13][14] At the end of the 2022 season, Arita had helped Iwaki gain promotion to the J2 League for the first time in their history contributing with 17 goals in 31 matches.