This is a request from @yuikuran1  who asked for a summary which I am glad to give. These are the bullet points

Yukimura knows that Rei is a girl but keeps it a secret

Rei is in the Intraschool ranking matches

Rei wins against Kirihara Akaya, obvious that she is better than him but because of Kirihara's ability, it ends up being really bloody

Kirihara gets yelled at by Sanada

Rei visits Yukimura and he explains that he knows that she is a girl

There is animosity against Rei and Kirihara

Hard training leaves Rei exhausted making Ryoma worry about her

Rei meets Seigaku and she is reminded of her group, she becomes friends but they don't know that she's from Rikkai Dai Fuzoku Chuu

Rei goes but against Momo and wins leaving them shellshocked

Rei has a tennis match with Ryoma and learns his moves but recreate them as her own

The district tournaments begin and this is the order (Singles and Doubles)

Single 1) Sanada Genichiro 
Single 2) Yangai Renji
Singles 3) Echizen Rei
Doubles 1) Niō Masaharu/ Yagyū  Hiroshi
Doubles 2) Marui Bunta/ Jackal Kuwahara

Rikkaidai wins, they are still amazing like before. Rei watches Seigaku matches but no one sees her.

Afterwards the team bonds, Kirihara doesn't like Rei though. Rei continues to visit Yukimura and they bond.

Intraschool match l

Kirihara wins against Jackal but losses against Rei.

Rei wins against Yagyū but loses against Sanada. Brutal defeat from Sanada which leaves Rei crushed. Rei meets up again with Seigaku and talks to Ryoma and the rest of the team.

Yagyū loses against Jackal. Training Session continues

Preliminary begin

Single 1) Sanada Genichiro 
Single 2) Yangai Renji
Singles 3)  Kirihara Akaya
Doubles 1) Marui Bunta / Jackal Kuwahara
Doubles 2) Echizen Rei/ Niō Masaharu

Rikkaidai wins no contest (It's how they are in the anime and manga, super strong)

Rei watches Seigaku's match and Momo notices her for a second. Rei joins in on Seigaku's training until Fuji and Tezuya see her. Rei and Ryoma have a match together. Rei loses against him and Rei is crushed.

Momo mentions seeing her and they are cautious towards her.

The Preliminaries finish and Rikkaidai trains.

Intraschool match ll

Rei tries to go against Sanda but is shut down. She tries against Yangai but losses. Yangai realizes that she is a girl but says nothing about it. Kirihara wins against Rei. She decides to sit out from the upcoming tournament. Rei tells Yukimura about the match and he gives her advice. The two grow closer.

Tournament continues

Single 1) Sanada Genichiro 
Single 2) Yangai Renji
Singles 3) Kirihara Akaya
Doubles 1) Niō Masaharu/ Yagyū  Hiroshi
Doubles 2) Marui Bunta/ Jackal Kuwahara

Yukimura gets worse and the whole team visits him together he tells them the bad news. The team promises to win the Nationals for the third time. The team finds out she's a girl and accept her.

Tournament Semifinals continue

Single 1) Sanada Genichiro 
Single 2) Yangai Renji
Singles 3) Niō Masaharu
Doubles 1) Kirihara Akaya/Yagyū  Hiroshi
Doubles 2) Marui Bunta/ Jackal Kuwahara

Intraschool matches

Rei is stronger than ever and wants to go against Seigaku. The team is surprised at her strength. Rei wins against Niō and Marui. Kirihara and Rei have a match against each other and she wins against him in a close match. Sahara vows to have a match with her after the Kanto Regional Finals.

Kanto Regional Finals

Singles 1: Sanada Genichirō 5-7 Echizen Ryoma
Singles 2: Echizen Rei  5-7 Fuji Shūsuke
Singles 3: Yanagi Renji 6-7 (29-31) Inui Sadaharu
Doubles 1: Niō Masaharu/Yagyū Hiroshi 6-4 Oishi Shūichiro/Kikumaru Eiji
Doubles 2: Marui Bunta/Jackal Kuwahara 6-1(manga) 7-5(anime) Kaidō Kaoru/Momoshiro Takeshi

Yukimura is better after and comes back to the team. Sanda and Rei have a match and Rei wins. Yukimura has a match against Rei and the match lasts for a long time and Rei loses. The team trains and as the Nations come Rei and Yukimura have a final match. Rei wins against him 7-6 (33-31).

Nationals Begin

Finals

Singles 1: Echizen Rei 7-6 (55-53) Echizen Ryoma
Doubles 1: Marui Bunta/Jackal Kuwahara 5-7 Ooishi Shuuichirou/Kikumaru Eiji
Singles 2: Yukimura Seiichi  7-5 Fuji Shuusuke
Doubles 2: Yanagi Renji/Kirihara Akaya 5-1 (retired) Inui Sadaharu/Kaidou Kaoru
Singles 3: Sanada Genichirou 5-7 Tezuka Kunimitsu
Kirihara Akaya 6-7 (20-22) Momoshiro Takeshi

They go to the U-17 (?) with the High schoolers.

Yukimura and Rei are together.

Summary Ends