Washio Reina was born on January 20, 1994 in Saga Prefecture, Japan.
Prior to auditioning to LDH, she was a trainee of EXPG Fukuoka since her first year of high school. Washio dropped out from school at the first year of high school to focus on becoming a singer. In 2011, Washio applied to EXILE Presents VOCAL BATTLE AUDITION 3 ~For Girls~ in the vocal section.
On July 26, during an E-Girls SHOW event in SHIBUYA-AX, it was revealed that Washio was one of the winners of the VOCAL BATTLE AUDITION 3 and was added to FLOWER as a vocalist. On that same day, she was also added as a member of E-girls, having a concurrent position between the group and FLOWER.
On October 12, she made debut with FLOWER with the single "Still".
On September 30, she left Flower with the group's disbandment.
On December 22, with the announcement of E-girls' disbandment set for around the end of 2020, it was revealed that Washio will be making solo debut.
- Main article: List:Washio Reina Discography Featured In
- [2013.08.14] DJ DECKSTREAM - DECKSTREAM.JP (#12 Ano Hi no Sayonara feat. Washio Reina (Flower / E-girls))
- [2014.03.26] m-flo - FUTURE IS WOW (#12 d.w.m / m-flo + Reina Washio (Flower / E-girls))
- [2018.06.20] MACO - BEST LOVE MACO (#3 Dear My Friend feat. Washio Reina (E-girls / Flower))
- Solo Songs
-  Hitohira
- Main article: Washio Reina/Gallery
- Favorite artists: JUJU, Amuro Namie, Crystal Kay
- Favorite movies: Harry Potter, Meitantei Conan
- Favorite food: Nattou (Fermented soybeans)
- Favorite flower: Sunflowers
- Hobbies: Karaoke, Watching music videos, Gaming
- She is currently the only member to be vocally featured on all E-girls' a-side singles.
- She revealed on the TV show EG-style that one of her dreams is for E-girls do a dome tour and Flower do an arena tour.
- She started an Instagram account on July 27, 2017.
- She has a very good friendship with singer MACO. Their pairing name is called Washimaco (わしまこ). She also collaborated in MACO's song "Dear My Friend", released in June 2018.
- Her fans gave her the nickname Reichieru (れいちぇる). EXILE HIRO often calls Washio by the nickname Wasshi (わっしー).
- Former AKB48 member Maeda Atsuko revealed to be a fan of Washio and attended Flower's Flower LIVE TOUR 2015 "Hanadokei" on June 26 in Zepp Tokyo.
Oldest Member of E-girls
- ↑ Ｅ―ｇｉｒｌｓ鷲尾伶菜、きつくても波乱万丈でも選んだ道が自分の正解
- ↑ “EXILEの妹分”新生FLOWER、5人加入し9人体制で10月デビュー
- ↑ 鷲尾伶菜「LARME」に初登場「E-girlsとは違った一面」
- ↑ 鷲尾伶菜からファンの皆様へ
- ↑ E-girlsを応援してくださる皆様へ
- ↑ MACOとFlower鷲尾伶菜の“わしまこ”が仲良く「さしめし」
- ↑ 7.0 7.1 前田敦子、Flower鷲尾伶菜は「全てがどストライク」 豪華タッグに「最高の2人」の声
- ↑ http://archive.is/20151006074155/http://7gogo.jp/talks/ejH8omPfQGcc/3804
- ↑ https://twitter.com/Atsuko_100/status/614492282570436609