Idea 2 Genderbender

What if important characters got gender-bent and ended up with issei in a complete expansion of his harem. A female Gasper, female vali, female Dulio, female Kiba,etc... There are characters that would be better than others so I will go through my favorite ideas and maybe a author that's better than me can make use of them.

Female Kiba: Duh this is a given I mean the light novel already did this with the gender bending gun.

Female Gasper: Nothing changes... Almost Literally aside from Valerie having a new love interest.(also Issei)

Female Vali: I like the enemy to lover trope and it has already been done and it was amazing.

Female Dulio: Issei could bond with her over food since Cannon Dulio loves taste testing food to bring some back to the orphanages he visits. Have Issei introduce her to Japanese cuisine and take that romance from there. Maybe have them be a OP battle couple for heaven, or use their romance as a different way to connect heaven and hell for the peace treaty.

Female Azazel: I think it would be hilarious if Azazel just constantly made Issei nervous and flirted with him which eventually leads to a true bond and the relationship takes off when issei almost dies because of juggernaut drive and Azazel just cant stop worrying.

Female Sirzechs: Yes... Yes... YES!!! I love it overpowered girlfriends and a boyfriend who's learning the ropes; add in a jealous Rias and boom an amazing premises for a romcom. You can cause a funny scene by having Sirzechs disguise the cuddling she wanted to do with Issei as "training" it would be amazing. Have them meet by rias accidentally giving her familiar her sisters summoning circle instead of her own having issei meet Sirzechs first.

Female Micheal: ... I don't know how this would go but I think Issei would meet her at the shrine first and then she would get interested in him when he asks to allow Xenovia and Asia to pray even though they are devils. You could throw in Gabriel for a sister rivalry in the race for Issei's heart.

Female Arthur: Artoria Pendragon... Need I say more?

Female Bikou: Prankster monkey tries to prank him but it backfires in the most dxd way possible and go from their.

Female Draig: I just love this because Issei has been stated to be one of the few to truly treat Draig as a friend and not a weapon, and I think Draig being jealous that she can't hug him during the day and the other girls being jealous that Draig can hog Issei through his dreams is an interesting tool to cause harem fights.

Female Albion: ... I just think it would be funny if Albion somehow fell in love with her rivals host make it so both her and Vali are female and both want to learn more about him, boom all problems related to how it would work solved.

Female Saji: Surprised this hasn't been done yet. I believe it would start out as a rivalry like in canon but slowly and maybe through group training sessions she slowly falls for the hard working person we all know light novel Issei is. Also i think its funny how light novel Issei is a training maniac unlike anime Issei who just complains.

Female Great Red: Biker girl takes an interest in a kid who inspires many dreams in the children of the underworld, A love forms, Ophis doesn't like it. Maybe we get a Yandere Red who is obsessed with Issei cause he basically became one of her greatest sources of power who knows?

Female Hades: Issei gives her a defeat with Vali and it goes from Enemy to ally and from ally to lover. I think if Issei could somehow automate Hades work giving her more time for herself we would inadvertently get her appreciation and later love.

Female Ajuka: I think she would take an interest in Isseis ability to, in a lack of better terms, fuck logic in the ass. She would slowly try to "figure" him out and eventually it leads to short conversations about Isseis theories on magic, runes, and the gears, those conversations lead to brunch, which leads, to dinner, and it ends in her house.( ͡° ͜ʖ ͡°)

Female Crom Cruach: I think it would start from when he helped defeat her and she would take up training him cause she's bored and wants a good fight, but it would eventually lead to her being jealous of his relationship with the other girls leading to her confessing, and this all leads to adorable hatchlings in the later future.

Female Cao Cao: Tsundere who hates losing falls in love with the guy who kicks her shit in nuff said.

Female Sairoorg: He saved her mom, he defeated her, and he is genuinely a good guy. Recipe for love if you ask me. She would probably ask for him to train with her and since I use light novel issei he would agree so he can become stronger. One training session turns into two, then three, then seven, next thing they know they have a bond and she's in love.

Female Shiva: She gets interested in the fact that her ability to see the future blurs and brightens when he's around. Eventually she decides that he ends up hurt to much and that she'll protect him so he takes less injuries. It will eventually lead into her finding out things about not only him but her inner most feeling will also come to light. She can also help train him.

Female Indra: She does something stupid and ends up getting her ass beat by a female Shiva and Issei who were just trying to have a afternoon tea in between training sessions. Indra decides that to get Shiva weaker she should either kill Issei or steal him from Shiva. She tries to kill him but that proves to difficult since Shiva trained him herself so she goes with plan B. It backfires when she started spending time with him and slowly he starts changing her for the better. It leads to shiva and Indra agreeing to share him so they don't destroy the world fighting over Issei.