You can start by looking on popular fanfiction websites like Archive of Our Own (AO3). It has a large collection of various fanfictions, including ritsu x masamune ones.
Well, 'The Unspoken Love of Ritsu and Masamune' is also great. It delves deep into their unspoken feelings, slowly building up the tension and romance in a very believable way. It shows how their relationship could develop over time with all the little nuances and details.
Love and reconciliation are very common themes. Their relationship has a lot of history and baggage, so many fanfictions focus on them working through past issues to be together.
You can try some popular fanfiction websites like Archive of Our Own (AO3). It has a large collection of various fanfictions, including those of takano x ritsu. Just search for the relevant tags and you might find some great lemon fanfictions there.
One popular 'onodera ritsu x takano masamune fanfiction' is 'A New Beginning'. It shows their relationship developing in a modern AU setting. The author does a great job of capturing their personalities.
Fanfiction.net is also a great place to look for masamune x aki fanfiction. There are many writers who contribute to this pairing. However, the quality may vary, so you might need to read through a few to find the really good ones. You can also check out some dedicated anime or manga fanfiction forums where fans might share their works or recommend some good ones.
The theme of second chances also pops up a lot. Their relationship had a rocky start, and fanfics like to play with the idea of them getting a second chance at love. It gives the writers a chance to explore different ways their relationship could develop and how they can make it work this time around.
One great 'onodera ritsu x masamune takano fanfic' is 'A Chance Encounter'. It beautifully portrays their relationship with well - written dialogues and emotional depth. The author does a wonderful job of showing their evolving feelings for each other.
They have a complex and evolving relationship. Sometimes they are rivals, and at other times they show signs of understanding and connection.
You can try Archive of Our Own (AO3). It has a large collection of fanfictions from different fandoms, and there are likely many for this pairing. Fanfiction.net is also a good option, as it has been around for a long time and has a vast database.