Rengoku is often described as selfless, always putting others before himself, especially when it comes to protecting innocent people from demons. He's passionate and wholeheartedly devoted to being a demon slayer. He can be very boisterous and free-spirited, always offering compassion and kindness to those who need it. He's cheerfully eccentric, rarely showing any other emotion unless times call for it. He is family-oriented and caring. In the face of danger, he is bold and courageous.