Sen is a young man of medium height with dark, shaggy hair, and dark eyes, which are rather thin and lazy-looking. He seems to have a modest athletic build, the same as most of his classmates, and a slight tan.
His hero costume appears to be a dark-colored windbreaker with grey, drill patterned rings around the base of the neck and arms. Over this, he wears a large white trench coat and gloves.
Sen is a level-headed person who remains mostly calm and focused on many occasions. He is also shown to be more mature than Neito Monoma, telling the latter to quit provoking Katsuki Bakugo and focus on his goal during the Cavalry Battle.
Despite his serious demeanor, Sen can sometimes warm up during times when he drops his solemn behavior, such as when he shows enthusiasm in fighting against Mashirao Ojiro during the Joint Training Arc.
Volume 22 mentions that he's rather belligerent in terms of personality and often gets dragged along in his friends' antics. Sen is also described as an "ikeman", having the appearance of a good-looking man. 
Overall Abilities: Sen has proven to be a rather capable combatant who possesses a great handle on his Quirk, and some proficiency in close quarters combat. By using the gyrating effects of his Quirk in tandem with his hand-to-hand combat abilities, Sen can deliver powerful spinning attacks that can damage his enemies, which are amplified if he uses his drill gloves.
The effects of Gyrate turn Sen's limbs into something akin to large rotary tools. This enhances his hand-to-hand combat skills significantly.
|Harsh Way of Thinking||5/6 A|
Drill Gloves: Sen wears a pair of spiral-patterned gloves that cover only his fingers. These gloves increase Sen's offensive capabilities as they can be used to damage his foes greatly and make physically defending against his Quirk impractical. Thanks to his Gyrate Quirk, these spirals act like a drill and cut into an enemy.
Battles & Events
|Battles & Events|
- Sen likes cameras.
- Sen's surname contains the kanji for "revolve" (回 kai?) and "field" (原 bara?), and his first name contains "rotation" (旋 sen?).
- Sen's second English voice actor, Matt Shipman, also voices Inasa Yoarashi, Takeshita, and Mr. Brave.
- Sen's Quirk could be a reference to the powers of The Flash villain The Top.
|U.A. High School|
|Class 1-A Students||Denki Kaminari • Eijiro Kirishima • Fumikage Tokoyami • Hanta Sero • Izuku Midoriya • Katsuki Bakugo • Koji Koda • Kyoka Jiro • Mashirao Ojiro • Mezo Shoji • Mina Ashido • Minoru Mineta • Momo Yaoyorozu • Ochaco Uraraka • Rikido Sato • Shoto Todoroki • Tenya Ida • Toru Hagakure • Tsuyu Asui • Yuga Aoyama|
|Class 1-B Students||Hiryu Rin • Ibara Shiozaki • Itsuka Kendo • Juzo Honenuki • Jurota Shishida • Kinoko Komori • Kojiro Bondo • Kosei Tsuburaba • Manga Fukidashi • Neito Monoma • Nirengeki Shoda • Pony Tsunotori • Reiko Yanagi • Sen Kaibara • Setsuna Tokage • Shihai Kuroiro • Tetsutetsu Tetsutetsu • Togaru Kamakiri • Yosetsu Awase • Yui Kodai|
|Department of Support||Mei Hatsume • Bibimi Kenranzaki|
|General Department||Hitoshi Shinso • Chikuchi Togeike • Tsutsutaka Agoyamato|
|Second Year Students||Mawata Fuwa|
|Third Year Students||Mirio Togata • Nejire Hado • Tamaki Amajiki • Bibimi Kenranzaki • Yuyu Haya|
|Staff||All Might • Cementoss • Ectoplasm • Eraser Head • Hound Dog • Lunch Rush • Midnight • Nezu • Power Loader • Present Mic • Recovery Girl • Snipe • Thirteen • Vlad King • Gran Torino (Retired)|
|Former Students||All Might • Endeavor • Best Jeanist • Midnight • Eraser Head • Loud Cloud • Present Mic • Mister Blaster|
|Locations||Class 1-A • Class 1-B • Conference Room • Ground Beta • Ground Gamma • Ground Omega • Gym Gamma • Heights Alliance • Lunch Rush Cafeteria • P.E. Grounds • Recovery Girl's Nurse's Office • Sports Festival Stadium • Teachers Lounge • U.A.'s Development Studio • Unforeseen Simulation Joint|