Rias always not flirt with other boys because rias had secretly had a husband as it was you a guy, the handsome with silkskin pale, abs body, kind, helping and gentleman. Rias only show virginity only for you all day
Issei doesn't knew about it since issei is new in rias peerage in about 3 days being rias peerage. Rias doesn't had feeling for issei and issei is a pervert who like naked woman all day and peek woman naked or shirtless.
You having mission almost to finish mission cause your strongest cause you defeated an enemy in 1 hours fast, that is why your famous in underworld devil and heaven. When you came back to gremory place to surprised rias and gremory family your back.
3 DAYS MONTH You goes to school where rias go was a school to surprised rias, after you surprised rias. Kiba, koneko and akeno knew you are rias husband since you are a male, rias always spend time with you all day. Issei was confused, jealous and envy of you get his girl rias
You knew issei had buster dragon but your strongest then him. Issei envy getting stronger seeing rias flirt with you but not him at all, it strange to him now. Issei had enough of this, issei wanted rian in his harem
Issei decided approach rias alone at office and he wanted to know why rias always near you, rias look at issei burst in her office "something you need, isse?" rias state as her eyes glanced at issei in holding shoulders rias shoulders by kissing rias gently, rias strugling as pushing issei off to you
"what the hell, issei!!" rias yelled at issei had done to her "You been ignored me, why you always spend time with that guy diavolo, he's a new student here, rias!!?" issei state annoying and confused when he seeing rias, akeno, kiba, koneko, grafiya lucifuge rias sister in law and sirzechs lucifer grafiya husband, rias father zeoticus and rias mother venelana been with you
"because i am already married issei, diavolo is my husband!" rias state the the truth reveal that she is married "how long you married him, r-rias?" issei state, his eyes widened heard that rias already married
"Over 3 days ago, look Issei, your just a friends to me and my pawn but you had no right to kiss me" rias stated, as she sit back to couch and glared at him back, for what happen here in her damn office
"Behaves yourself, diavolo is a demon King rule at devildom so give respected, yes I am Queen of devildom, so give respected Issei" she sigh, getting bit headached at Issei mind inappropriately though