Sengoku is the pride of Yamabuki Middle School boy's tennis team. His innate talent in tennis allows him to be considered as one of the strongest and best players in the country. Sengoku believes that he is also very lucky, thus having the nickname "Lucky Sengoku". However his "luck" doesn't seem to work out well with girls.
Sengoku is a happy-go-lucky kind of guy and is a huge flirt.
He is very laid-back and likes to tease others. When he was first introduced, he was up and about scouting cute girls at the Seigaku Girls' tennis club. Sengoku is extremely careful with his womanizing ways though because he does not want to pick one girl over the others according to Shintenhoji's Konjiki. Sengoku can also be quite the slacker and can happily skip practice without a care in the world if he wants to.
Despite his carefree personality Sengoku is quite ferocious once he puts his mind to things. Although no matter how determined he is, he will always be easily distracted by girls.
One Year Prior To The Storyline
Nicknamed by his peers because of his insurmountable good luck, Lucky Sengoku had the opportunity last year to replace Kunimitsu Tezuka at the Jr. Senbatsu Training Camp after the latter refused the invitation. Unfortunately, Sengoku appeared to have used up his luck this year, losing two highly-contested matches.
Tokyo Prefecturals
Sengoku appears during the start of the Tokyo Prefectural Tournament and talks briefly with some Seigaku regulars.
Sengoku and Yamabuki power their way through to the Semifinals of the Tokyo Prefectural Tournament and meet underdogs Fudomine Junior High who had already caused an upset in the tournament. However Yamabuki did not have to go through a long match with Fudomine as Ibu Shinji suffered an injury before the match making him forfeit meaning Yamabuki were gifted an extra win and were able to easily reach the Finals of the Tokyo Tournament where they met Seigaku in the Finals.
After winning, surprisingly, Doubles 2 but losing in Doubles 1, in Singles 3, Sengoku takes on Momoshiro Takeshi. Even though he led 5-0 in the end he loses to Momoshiro 5-7 causing Seigaku to lead 2-1.
Regionals
He and Yamabuki went to the Regionals and cruised through to the Quarter-finals.
After his loss to Kamio Akira, Sengoku took a short break to reinvent his tennis and returned anew, helping Yamabuki to the Nationals.
Regional Select Invitationals Camp
This is an anime exclusive arc. Sengoku Kiyosumi along with several other players from the Kanto Region accepts an invitation to the Junior Kanto Regional Select Camp. He trains with several other players there and is amongst the Eight players selected to represent the Junior Kanto Japan region against the Junior West Coast USA region. During the camp he and Momoshiro Takeshi have a match during training that Sengoku wins confidently 6-3.
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