From MangaHelpers:
When her parents went overseas, Nagamori Konoka moved in with her aunt and her cousin, Itsuki. Konoka is excited to transfer into this new school and start her new school life, but she starts off her first day by being late to class!
When she learns that her cousin is in the tennis club, she eagerly decides to join the girls tennis club. Konoka has never played tennis before, and she is taken aback to see how highly skilled the other girls are. When she tries hitting a few balls, though, Konoka surprises everyone with her amazing natural talent.
Konoka begins to make friends with the girls on the tennis team, especially the captain, Kyoka. The one teammate who doesn't seem to want to be her friend is her classmate Mizuki, who is skilled at tennis but very standoffish. Will Konoka be able to make friends with everyone and enjoy her tennis-filled life to the fullest?