I'd recommend 'Fruits Basket'. There are moments when certain male characters come to the rescue of the female ones, showing protective instincts. The series is known for its heartwarming and emotional moments.
Well, usually there's a sense of danger for the girl and the guy's determination to keep her safe. Also, there might be some kind of developing romance between them.
One popular 'guy protects girl' fanfic could be in the 'Twilight' fandom. In many fan - made stories, Edward might be protecting Bella in different, more creative scenarios than in the original books. For example, protecting her from new supernatural threats in Forks.
It could be a fantasy manga where the guy has special abilities to keep the girls safe.
One such manga is 'Hana Kimi'. The story is engaging and the crossdressing element adds a unique twist.
One such manga could be 'Monster Love.' In it, the tough and intimidating male lead develops feelings for the kind and gentle female character.
Add unexpected twists. For example, the girl could turn out to have some hidden power that she reveals while being protected, which then helps the guy in turn. This flips the dynamic a bit.
You might want to check out 'Toradora!'. The male lead's attempts to win over the female lead make for an engaging read. The character development and plot twists keep you hooked.
Self-discovery is a big part. The character explores their new identity and what it means for them. Also, social reactions and challenges can be a theme, like facing prejudice or trying to fit in.
Often, there's a focus on the character's adjustment to their new gender identity and the challenges that come with it. Also, there might be romantic elements as they navigate this new life.
It could lead to all sorts of interesting plot developments. Maybe it'll cause confusion among their friends or bring out new sides of their personalities.