Some themes include the transformation process. If Cloud becomes a vampire, the fanfiction might explore how he deals with the physical and emotional changes. It could be a very painful and confusing time for him. And of course, there's the theme of protection. Cloud, even as a vampire, would likely feel a strong need to protect Tifa from other vampires or threats in the vampire world. This theme can drive a lot of the action and plot in the fanfiction.
I'm not sure specifically which are the most popular ones. You could try searching on fanfiction websites like Archive of Our Own. They usually have a large collection of such stories and you can filter by popularity, ratings, etc.
There's a fanfiction where Cloud and Tifa start a family. It delves into how they adjust to domestic life while still having to deal with the remnants of their past battles. It shows a different side of their relationship, more tender and family - oriented.
Love and relationships are common themes. There could be romantic love triangles between Cloud, Tifa and Aerith, or platonic love that shows their deep friendship. Another theme is self - discovery. Each character has their own journey of finding out who they really are. Cloud is often on a quest to understand his true identity, Tifa with her own sense of self in relation to her past and Aerith with her Cetra identity.
One common theme is the exploration of their unspoken love. In the game, their relationship is complex and full of nuances, and fanfiction often dives deeper into those unexpressed feelings. For example, how they might be secretly in love but too shy or preoccupied to admit it.
One common theme could be the struggle with inner demons. Cloud might be dealing with his muddled past and identity issues while Tifa is trying to support him, all in the context of a somewhat depressive atmosphere. Another theme could be the sense of isolation they might feel from the rest of the world. They are often outsiders in the complex world of FFVII, and this can be exacerbated in a fanfiction focused on depression.
One popular theme could be adventure. Since Tifa is a strong character from a game world, fanfictions might explore her going on new adventures. Another theme could be friendship, perhaps showing her deepening her bonds with other characters. And of course, romance is also a common theme, exploring her relationships in a more in - depth and creative way.
Some fanfictions also focus on Tifa's backstory. They might explore her childhood, how she grew up and trained, and how those experiences shaped the person she became in the main story. This gives readers a deeper understanding of her character.
One great Cloud Tifa fanfiction could be 'The Reunion'. It beautifully depicts their relationship after a long separation. The author does a wonderful job of showing their deep emotional connection.
There are fanfictions that focus on their past. Maybe a story that dives into their childhood memories. How they first met, and the little things that made them friends back then. This could add more depth to their relationship in the present. For instance, a story could show how a small incident from their childhood influenced their actions towards each other during a crucial moment in the main story.
One common theme is unrequited love. For example, in some fanfictions, Tifa might feel that Cloud's attention is more on Aerith, leading to her heartache. Another theme is sacrifice. Aerith, knowing Cloud has feelings for Tifa as well, may sacrifice her own feelings for the greater good. Also, the theme of confusion is often present. Cloud himself is often portrayed as being confused about his true feelings for both women. He may love Tifa for their long - standing bond, but also be attracted to Aerith's different qualities.