Naruto is often paired with Gaara in these fanfictions. Their strong bond in the original series makes it interesting to see how they interact when Gaara time - travels. Naruto could be the one to help Gaara adjust to a new time period or vice versa.
Often, Naruto's female characters are paired with Gaara. For example, Hinata. Since Hinata is a kind - hearted and shy character, her relationship with the initially cold - hearted Gaara could be an interesting exploration of how two different personalities come together.
Naruto could still be a main character. Their relationship would likely be different if Gaara were a girl. Maybe Naruto would be more protective of her.
It could be Orochimaru. He might manipulate Gaara into kidnapping Sakura. Orochimaru could have his own devious plans for Sakura, like using her medical knowledge for his experiments. So, he uses Gaara's power and his somewhat unstable mental state at times to achieve his goal. Then Sakura and Gaara would have to team up to fight against Orochimaru.
Since we don't know the specific 'gaara love story', it could be Gaara himself and perhaps a female ninja from his village. Maybe it's a story where he falls in love with someone who has been by his side during his journey of self - discovery.
One possible story could be that Sakura goes to the Sand Village for a medical mission while Gaara is Kazekage. They start to interact more, and Gaara is impressed by Sakura's strength and kindness. Eventually, they form a strong friendship that helps in strengthening the bond between the Leaf and Sand villages.
The main characters are clearly Gaara and Tenten. Gaara is from the Sand Village, known for his control over sand and his complex past. Tenten is from Konoha, a skilled weapons - master. In this fanfiction, they are the focus, and their relationship development, whether it be friendship turning into love or a more sudden romantic connection, is what the story is likely to revolve around.
In the 'sad gaara love story', Gaara is surely a main character. The other main character could be someone who is kind - hearted and initially attracted to Gaara's hidden vulnerability. Maybe it's a healer in the village who tries to help Gaara deal with his emotional wounds and in the process, they fall in love. But their relationship is doomed to be sad for some reasons.
The main characters are clearly Gaara and Sakura. Gaara, the once - lonely and misunderstood shinobi from Sunagakure, with his unique sand abilities. And Sakura, the intelligent and strong - willed kunoichi from Konohagakure, known for her medical ninjutsu and her growth as a fighter.