Sasame is a man of average to above-average height and athletic build. He has light hair, short or shaved except for a light sweep at his front. According to Yoshikage Kira, he has a very visible tan that causes him to stand out.
In a flashback to his meeting with Kira, he wears a tan wetsuit. While eating in the ramen shop, he is bare-chested, only wearing some sort of puffer vest.
When he meets Josuke, he is wearing a shirt with a bowtie, along with a jacket and gloves. All of his clothes have his Stand's "Q"-like symbol patterned across them.
Sasame has strong sadistic tendencies, having used his Stand to toy with or torture or kill a girl who went to see him at the beach. He is consumed with a desire for revenge against Yoshikage Kira.
Sasame is proud of being a surfer, happy to call it his job.
- Main article: Fun Fun Fun
Sasame's Stand is Fun Fun Fun, with the ability to control the body of a person underneath him.
Sasame developed a Stand in his childhood after the house where he grew up was completely leveled by the earthquake and one of the Wall Eyes rose on that spot.
Sasame, in his adult life, was confronted by Yoshikage Kira at the beach. Kira, appearing from behind Sasame, insulted his occupation as a surfer by questioning whether surfers were men of the sea or men of the land. Kira later encountered him in a ramen shop near a port, and relayed the same question. After warning him to stay away from the coast, Kira then forced Sasame to leave by inserting an explosive bubble within his face. As he ran out, Sasame accidentally bumped into Josefumi Kujo, causing the latter to spill an excessive amount of pepper into his ramen.
Some time after this encounter, Kira convinced Sasame to eat all of his fingers under the influence of alcohol.
After this incident, Sasame swore revenge on Kira and was the one responsible for setting all the traps in the apartment room, planning to attack Kira when he returned. Additionally, in order to remove anyone who might be associated with Kira, Sasame planted photo albums of bound women in the apartment.
He initially mistakes the protagonist to be Kira, attempting to kill him with his Stand. Once defeated, he realizes his mistake, while still acknowledging a certain familiarity. He explains that he is not Kira, along with his grudge against the latter. Following the interrogation, he is then knocked out.