Obviously, Romeo would be the main character. Then there could be characters like Wendy, who is young and has healing magic. Her gentle nature could be an interesting addition to the harem. Another potential character could be Levy, with her intelligence and book - smart magic skills.
Obviously, Ichigo himself is a central character. From Fairy Tail, characters like Lucy could be part of the harem. Her kind and adventurous nature might be attracted to Ichigo's strength and sense of duty. Erza could also be there, with her strong - willed and powerful personality being drawn to Ichigo's unique abilities. And Wendy, given her gentle and healing nature, might also find herself interested in Ichigo.
One of the most commonly paired characters with Romeo is Natsu. Natsu is a very popular character in Fairy Tail, and some fanfiction writers like to explore a yaoi relationship between him and Romeo. Their different personalities, with Natsu being more hot - headed and Romeo being a bit more level - headed at times, can create an interesting dynamic.
Wendy is another character. She and Romeo can be portrayed as good friends. They might go on adventures together where Wendy uses her healing magic to keep Romeo safe during battles.
Natsu is often paired with Romeo in some fanfictions. Natsu can act as a mentor figure to Romeo, teaching him new fire - based magic techniques. Their interactions can be really exciting as they both have a passion for magic.
One idea could be Romeo going on a magical adventure with his harem members to save the Fairy Tail guild from a new dark threat. They might use their combined magical abilities to overcome obstacles.
Lucy could also be a love interest in some fanfiction scenarios. Even though there is an age difference, Romeo has always looked up to Lucy as a strong and beautiful mage in Fairy Tail. In a fanfiction, this admiration could turn into a more romantic feeling as Romeo matures and proves himself to be a worthy mage.
Lucy is definitely one of the most common. She has a close bond with Natsu from the start of the series. Erza is also often included. Her strong and confident personality makes her a great addition to the harem. Wendy could also be part of it. Despite her young age, she has a deep respect and admiration for Natsu.
There could be a mysterious old wizard who takes Natsu under his wing when he leaves Fairy Tail. This wizard might have knowledge of ancient magics that Natsu is eager to learn.
Gray and Juvia's offspring could also be central characters. They could have an interesting mix of ice - make magic and water magic. Maybe they struggle with controlling their powers at first, just like their parents did, but in different ways. And their relationships with the other next - generation characters could be complex, adding depth to the story.
The children of Natsu and Lucy would be great main characters. They could inherit their parents' powers and personalities. For instance, having the same determination as Natsu and the intelligence of Lucy.