Taihei is a kind and hard-working person who loves to cook. He is well known for being a pushover and excessively tolerant of other people slacking off, such as Umaru or his co-worker, Takeshi Motoba.

Taihei, while polite and well balanced, is described as a bit of a doormat, as his younger sister constantly relies on him, making him cook, clean, buy, and do whatever she tells him to. Though Umaru may be unbearable at times, Taihei appears to deeply care for his sister and worries about her future as an independent person, admitting that he has spoiled her for too long. Although Taihei does internally express anger towards Umaru during her more unbearable moments, he often calms down and tries to take a friendlier approach to winning her happiness back, which he always succeeds in doing.

At times, Taihei seems to have trouble with remembering certain things in his past, a result of a possible long-term memory deficiency. Umaru seems to take the place in his mind of the people he has forgotten.

Taihei is often gullible and is easily duped into doing whatever Umaru tells him to, especially in the presence of peer pressure, which he is extremely sensitive to. In one instance, she made him miss work so he could help her win a Necolumbus, covering up her motive by convincing him to use that time as a form of relaxation when in actuality, she tricked him into helping her and improve her odds of winning.

Even though he seems very sensitive to other people's feelings, he has also shown to be especially oblivious to others' love interests, as shown when he does not realize both Kanau and Ebina have feelings for him.