One of the most common female characters is likely Hinata. Her shy but strong - willed nature can be explored further in an Anbu Harem Fanfiction. She could be part of the Anbu for some reason in the fanfiction, perhaps to protect Naruto or because of her own growth as a ninja. Then there's Tsunade. Although she is older, in fanfiction, she can be reimagined in a different way. Maybe she takes a special interest in Naruto's progress in the Anbu and gradually develops feelings for him. Also, some female Anbu members that are only briefly mentioned or not at all in the original series can be fully developed in these fanfictions and become part of Naruto's harem.
Hinata is often a common character. Given her long - standing feelings for Naruto in the original series, it's easy to incorporate her into an Anbu Harem scenario. Sakura can also be a part of it. She's a strong female ninja, and her relationship with Naruto in the canon can be tweaked in the fanfiction to fit the harem concept. Ino is another possibility. She has her own charm and skills, and in a fanfiction setting, she could be attracted to Naruto within the Anbu context. Also, some original female characters created specifically for the fanfiction might be included to add more variety to the harem.
Kurenai could be one. She has the skills and a mysterious side that would fit well as an ANBU. Her relationship with Naruto could start from her seeing his potential and gradually developing deeper feelings.
Kakashi Hatake is often a very popular character in ANBU - related fanfictions. His skills and mysterious past make him an interesting subject. Another popular one is Itachi Uchiha. Given his complex character and his time in the ANBU, he is a common focus. And Yamato is also quite popular as he has his own unique abilities and his role within the ANBU and in relation to Naruto.
Tsunade from Naruto is also a popular choice. She is a strong and mature character, which provides a contrast to some of the younger female characters. In One Punch Man, Tatsumaki is another one that is frequently part of the harem. Her powerful psychic abilities and somewhat tsundere personality add complexity to the relationships in the fanfiction.
Well, Naruto himself is obviously a central character. Then there are often female characters like Sakura, Hinata, and Ino. Sakura might be written as more aggressive in her pursuit of Naruto in the harem scenario. Hinata could be the shy but very loyal one, and Ino might bring a bit of sass and competition to the group.
In these fanfictions, Naruto himself is very common. Since it's a Naruto - Overlord crossover harem fanfiction, he is often the central male character around which the harem forms. Then there are female characters like Hinata from Naruto. From the Overlord universe, Albedo is often used. She has a strong personality and her appearance makes her a popular choice to be part of the harem.
Haku could be a character that appears in some Naruto Root Anbu fanfictions. Since he was a skilled ninja with a tragic backstory, some fanfictions might incorporate him into the Root Anbu, either as a new recruit or as someone who has a connection to the organization. It can add a new dimension to his character.
Hinata is often a part of the harem. In the original series, she has strong feelings for Naruto. Sakura can also be included. Even though she had feelings for Sasuke initially, in fanfiction, she can end up in Naruto's harem. Tenten is another character that might be written into the harem, as she is a strong and independent kunoichi.
Often, you'll see Hinata as part of the harem. Her shy nature contrasts with Naruto's more bold Mokuton - using self. Sakura might also be there, adding an interesting dynamic as she has her own history with Naruto. And then there could be some original characters created just for the fanfiction to add more flavor to the harem.
Hinata is another popular character in the harem. Her shy yet strong - willed nature makes her an appealing character. During the Chunin Exams, her Byakugan abilities can be used in really interesting ways in the fanfictions, like detecting hidden traps or opponents' weaknesses.
For Ichigo's harem, Orihime and Rukia are very common. Orihime with her kind heart and strong powers of healing, and Rukia being the one who introduced Ichigo to the world of Soul Reapers. In Naruto's case, Hinata and Sakura are often part of his harem. Hinata because of her long - standing love for Naruto, and Sakura being one of Naruto's closest friends.