Mitsugu Jinnai is a supporting character introduced in Fafner EXODUS, the sequel to the original Fafner in the Azure series. He is a resident of Tatsumiyajima, the island that serves as humanity's last bastion against the alien Festum. In his first appearance, he goes by boat to retrieve Kyousuke Mizoguchi after a battle, and during the rescue he spots a massive Festum behind Kyousuke, though both return safely. This demonstrates his willingness to place himself in danger to aid the young Fafner pilots. Later, when a boy named Leo is selected as a Fafner pilot, Jinnai passes down a treasured ancestral sword, telling Leo to prove to the Festum that he is the descendant of a samurai with the soul of a lion. This act reveals Jinnai’s deep sense of tradition, pride in his lineage, and his belief that the pilots must carry forward a warrior spirit. His personality is defined by courage, loyalty, and a quiet respect for heritage. Within the story, he functions as a figure who supports the core pilots from the sidelines, offering practical help and symbolic encouragement. His role expands in later installments such as Fafner: The Beyond, where his connection to Leo and his sword continues to represent the passing of resolve from one generation to the next. While not a frontline combatant, Jinnai contributes to the morale and cultural identity of the island’s defenders.