Sawai is a pacifist at heart, but also a rationalist in the face of the dangers that threaten humanity.
In the 21th century, Sawai was a secretary general at the United World and thus advocated the formation of TPC, being the head and founder of the said organization and a strong advocate of GUTS. The reason for oftenly participated in field operations is due to Sawai being dedicated in making contact with extraterrestrial life.
During Gatanothor's descent, Sawai ordered the evacuation of all personnel in the Dive Hangar to the Artdessei after Gatanothor's darkness had reached the base. He ordered Tetsuji Yoshioka to evacuate after the latter had declared his intent to sink alongside the base, calling him a fool to throw his life away. Sawai then watched Tiga's battle with Gatanothor and eventually came to learn that Daigo was Tiga after the Ultra's defeat and Rena's proclamation. Later on, he recruited Keigo Masaki to participate in the campaign to revive Tiga by using the light-gene converter to deliver the light to the Ultra. After Gatanothor's death, Sawai congratulated Keigo for his efforts and celebrated humanities' victory with his allies.
During General Koki Fukami's visit to the Mars Base in episode 1, it is revealed that Sawai's health had deteriorated since his time as the General. Regardless, he still wishes to inspect the Mars Base once his health improves.
Sawai visited the Mars Base for the first time on Februrary 2nd, 2019.
During the final operation against Gransphere, Sawai (along with Iruma) is present in the Super GUTS command center where he offers Fukami words of advice; and tells him to have faith in the subordinates that have supported him. After the defeat of Gransphere through the sacrifice of Shin Asuka, Sawai (and the other Chief Officers) can be seen thanking Super GUTS for their efforts; while also honoring Asuka's sacrifice.