TV Special
Description
Tōma Amagase spearheads the male idol unit Jupiter. Initially part of 961 Production alongside Shouta Mitarai and Hokuto Ijuuin, he exhibited a fiercely competitive and intense drive, singularly focused on becoming the top idol. This ambition fueled hostility towards rival units like 765 Production's Ryuuguu Komachi and the main idols, whom he dismissed as weak opponents playing childish games, openly insulting their level and sense of unity. His perspective was shaped by misinformation from 961's president, Kuroi, who portrayed 765 Pro as shady. Despite his abrasive nature, he possessed strong solo idol skills and refused unethical tactics. Defeat by 765 Pro revealed the importance of genuine unity, prompting Tōma and Jupiter to leave 961 Production and deeply reflect on their flawed unit dynamics.

Operating independently post-departure, Jupiter performed in small venues with volunteer staff, rejecting agency offers including persistent ones from Takashi Saito of the new 315 Production. Their outlook shifted after encountering fans unable to enter an overcrowded concert due to poor communication. A chance meeting with 765 Pro's Haruka Amami, where Tōma confidently declared Jupiter would surpass them despite starting over, renewed his commitment to properly connecting with fans. This led Jupiter to join 315 Production for a fresh, ethical start. Post-transfer, Tōma retained his passionate, top-idol ambition but became noticeably more cheerful and fulfilled. He embraced mentoring newer idols like DRAMATIC STARS (Teru Tendo, Tsubasa Kashiwagi, Kaoru Sakuraba), whom he met upon joining 315 Pro. His straightforward personality made him a target for good-natured teasing from unit mates Hokuto, whom he criticized as an annoying playboy, and Shouta, whom he called excessively loud or lethargic, while still acknowledging their essential talents and reliability.

Living alone with his father after losing his mother young, Tōma was scouted by Kuroi after winning his vocal contest. Beyond idol work, he avidly collects robot anime figures, displaying expertise that stopped Shouta discarding packaging. He excels at cooking, specializing in curry made from spices; rice and curry is his signature dish, frequently prepared for others, impressing fellow idol Soichiro Shinonome enough to suggest a chef career. He also enjoys soccer, dedicatedly supporting the professional Aoi twins, decorating his room with their posters and autographs. His development includes overcoming awkwardness in gravure shoots and romantic scenarios, often flustering during interactions with women, as seen during SideM's White Day 2015. He deeply cares for fans, sometimes pushing himself to injury for performances. His journey shifted from a solitary, win-at-all-costs mentality to embracing teamwork and genuine connections, while maintaining his core determination to be the best idol with integrity.

He appears in the special episode "315 Variety Pack! Made In Passion!", an unaired episode included with the seventh Blu-ray/DVD volume of THE iDOLM@STER SideM anime series.