Hiroto is the last secondary character to join the group, becoming a member only halfway through the game. He is known for saying "Heh..." before every line he speaks, and being extravagantly self-absorbed. He believes far too much in his own ability to fight, claiming he is the entire reason why the group will succeed, despite having the weakest non-soldier drone for most of the game, although his drone has an equal penchant for avoiding battle lines in favor of someone else recieving damage during the enemy turn.
He believes very strongly in true hard work, and most probably exudes such self-confidence because he believes a confident, hard-working person will succeed at all they want to in life, and fulfill all their dreams. He carries with him an expensive violin which was owned by a famous violinist, in playing position, and presumably plays music while talking and idling in his drone. His dream is to become a famous violinist, himself. He comes from a very rich family he calls "upper class", but doesn't want their money to attribute to his success.
His drone is Hopp-R, a locust. Ironically, 'locust' is just another name for grasshopper, which is a more recognizable, affirming, and accurate name for the drone, and would've been more amusing with how Hiroto 'named' his own. It is an extremely weak drone due to how level up works and has low general stats, and is dominantly an exceptional gun drone, but as the stats equalize and equipment unbalances further in the game, the locust becomes an exceptional cannon drone instead, especially in the endgame Badlands with the FCS'.
As soon as he appears, Tsubasa immediately remarks on if he really has to join the group, and none of the others seem very comfortable or nice around him either, with the obvious exception of Yamato, who thinks Hiroto's beliefs in dreams coming true and wanting to be famous is very admirable and impressive.
He is unique in that he only has 2 sprites, one with his eyes closed, and one with his eye open for at the end of every line. His decommission quote "Heh... That's enough of that." can be particularly irritating in the middle of a humiliating defeat.