In 2012, Okada participated in the "Tanaka Reina to Band Yaritai Joshi Member Daiboshuu" audition and successfully passed. On November 18, she was announced as a member of Reina's Band, later named LoVendoЯ, as a guitarist.
Starting from April 1, 2017, she became a regular on the ANIMAX show Game★Maniacs.
After the release events for Яe:Start were held in November 2017, LoVendoЯ ceased performing as a band, and did not have any activities together as a band after their radio shows ended in 2018. During the band's time of inactivity, Okada Marina and Miyazawa Marin performed as their duo Okamarin (おかまりん).
In August 2018, Miyazawa did cosplay modelling as the character Gladion from Pokémon Sun & Moon for Takara Tomy's official Z-Power Ring toy.
On March 31, 2019, she made a surprise appearance in the Hello! Project 20th Anniversary!! Hello! Project Hina Fes 2019, playing the guitar for BEYOOOOONDS' "Atsui!" performance.
On June 28, 2019, it was announced that LoVendoЯ would be suspending all activities at the end of July. It was also announced that Miyazawa Marin would leave UP-FRONT CREATE at the end of July following the expiration of her exclusive management contract with the agency.
Her last live, titled Miyazawa Marin Last Live Shin'en no Kikan ~Subete no Hito ni Kansha wo Komete~, was held on July 30, 2019 at SHIBUYA TAKE OFF 7 with former LoVendoЯ member Uozumi Yuki as one of the supporting guitarists. Former LoVendoЯ vocalist Okada Marina also appeared at the live as a guest.
- Name: Miyazawa Marin (宮澤茉凛)
- Nickname: Marin (まりん), Mofuo (もふお)
- Birthdate: April 10, 1993
- Birthplace: Miyagi, Japan
- Height: 164.1cm
- Blood type: A
- UP-FRONT GROUP status:
- Favorite Artists: MR.BIG
- Favorite Pokemon: Charizard
- Favorite Starter Pokemon: Charmander
- Admires: Michishige Sayumi
- Audition Song: "Jishin Motte Yume wo Motte Tobitatsu Kara" (guitar)
Discography Featured In
- UNDERGROUNDER (composition)
- Princess of lone castle ~ Koujou no Himegimi ~ (composition, arrangement)
- YELL ~Anata ni Okuru~ (composition)
- Answer (アンサー) (composition)
- Invisible (lyrics)
- Sazanami (さざなみ) (lyrics)
- Tobikiri no Christmas (とびきりのクリスマス) (lyrics)
- [2014–2019] The Girls Live
- [2017–2019] Game★Maniacs (ゲーム★マニアックス)
- [2013–2018] LoVendoЯ no Love On! (LoVendoЯのらぶおん！; LoVendoЯ's Love Sound)
- [2013–2018] LoVendoЯ no LV-Я (LoVendoЯのLV-Я; LoVendoЯ's Level-Я)
- [2013–2014] UF LICKS
- [2014–2016] MUSIC+
- [2016–2019] Upcoming
-  Miroku Jouhou Service "Keiri Man" (ミロク情報サービス「経理マン」)
- She has five cats.
- She loves animals.
- She had five years of guitar-playing experience when she joined LoVendoЯ.
- Her favorite music genres are hard rock and heavy metal.
- She is a fan of Mr.BIG, Night Ranger, Michael Schenker, Pantera.
- She is a Pokémon otaku and often draws Pokémon characters.
- Her favorite Pokémon is Charizard, and her first Pokémon was Charmander.
- Her favorite Pokémon character is James from Team Rocket.
- She owns a Nintendo 3DS, on which she plays Pokémon video games.
- Miyazawa cosplays a lot on her time off. She has been Gladion, Touko, and Green from the Pokémon franchise; Ginigstune (Silver Fox) from Kemono Friends; and for the 2017 Natsu Comiket, she went as Natsume Takashi from Natsume Yuujinchou.
- She befriended Yanagawa Nanami due to their mutual interest in Pokémon.
- "ミロク情報サービスCM 「経理マン」篇（30秒）" (in Japanese). Miroku Jouhou Service (via YouTube). 2015-05-14.
- "ミロク情報サービスCM 「経理マン（マイナンバー）」篇（15秒）" (in Japanese). Miroku Jouhou Service (via YouTube). 2015-12-25.
- "芸能界“最強ゲームチーム”を決定する「第1回 eスポーツ スターバトル チャンピオンシップ」開催決定" (in Japanese). GAME Watch. 2017-12-20.
- "LoVendoЯに関するお知らせ" (in Japanese). LoVendoR Official Website. 2019-06-28.
- "「宮澤茉凜ラストライブ 深淵の帰還 ～全ての人に感謝を込めて～」FC先行受付のお知らせ" (in Japanese). M-line club official site. 2019-06-28.
- Miyazawa Marin. "BD event by MIYAZAWA" (in Japanese). LoVendoЯ Official Blog. 2017-01-12.
- Yanagawa Nanami. "祝！宮澤さんと念願の♡梁川奈々美" (in Japanese). Country Girls Official Blog. 2017-05-16.