|Kanji||児玉 磊（こだま らい）|
|Likes||mommy; squid shiogara|
|Dislikes||boring adults; shellfish shiogara|
|Affiliation||Honwaka Daycare Centre|
|Relatives||Takeshi Kongou (father)|
Aiko Tsukishima (mother)
Akira Kongou (uncle)
Kodama Haruka (adoptive mother)
|Manga Debut||Chapter 20|
Takeshi's son who looks like a mini version of him. He is friends with Tsukimi and acts like Akira. He uses Takeshi's phase "Don't sweat the small stuff". Rai can also use the Double Hammer but his is far weaker than Akira's since he is still a kindergardener.
Rai was born to the gang leader Aiko Tsukishima who had a loving relationship with his father Takeshi but Takeshi left for unknown reason possible leaving for the 23 District Project but his mother Aiko never blame him because he had his way of life. When his mother gave birth to him she was dying and told Haruka to take care of him as his mother and she did.
Unknown Relative ArcEdit
He first appeared in this arc with Tsukimi in the kindergarten school playing with her in the sandbox but when her sister Hinako came in, she was shocked to see a "tiny Kongou" but Tsukimi explain it to Hinako that he is not him but Rai say it doesn't matter to him because he is he and Rai is Rai and told her not sweat about the small stuff. When they were waiting around for someone to pick Rai up Hinako was surprised and laughing how Rai and Akira are alike. But then Kiryu former underlings were causing problems in school and Rai got out to stop him and he did by using his Double Hammer! Hinako was shocked to know that Rai used Akira move. Then a women came by and started to sing a song and then the guy was paralyzed. Hinako was confused at who she is but then Rai ran to hear and yelled mommy which surprised Hinako a lot because she is very young? They later talk while walking home and the women named is Haruka Kodama and that she had Rai for five years and she only 18? But then Hinako mention Akira and show her the picture which Haruka was shocked and said to Rai they finally found Rai's father. Rai was shocked to see a picture of his father and wanted to go with his mother to beat him but Haruka put him to sleep to keep him away from the fight.
He is a combination of Akira and Takeshi when they were young. He loved his foster mother very much and says "don't sweat the small stuff" as his catch-phrase like his father did. Rai is easy going and loves sweet just like Akira. He seems to be fond of Tsukimi and in the finale, it seems like he wants to go out with her.
- Strength: 4/10
- Stamina: 3/10
- Spirit: 4/10
- Intelligence: 1/10
- Agility: 3/10
- Technique: 2/10
- Double Hammer: Rai can perform the same attack as his father and uncle, though much weaker, but still to the point of sending people many times larger than him flying.