Sengoku is a rather shy boy who gets embarrassed easily and the slightest thing will make him cower in fear, especially things to do with horror or insects. Sengoku is very smart and serious, normally ranked #1 in terms of grades in the school (and #2 in phys ed). He enjoys reading and has an incredible level of concentration while doing so, to the point of ignoring everything else going around him.

He is generally not very expressive with his emotions. The sole exception is his anger.