Ainz Ooal Gown: Supreme Being in DxD

Also, the pizza is burning in the oven

"Ahem... My deepest apologies for being late." A male voice rang in the silent classroom. "I have a message from the Student Council which explains the reason for my lateness as well as some things that have happened. Once again, I apologize for interrupting the class."

The boy offered a sealed letter with two hands and accompanied by a small bow, perfect form for someone handing a calling card or a gift.

The homeroom teacher of class 3-B took the letter with shaky hands, eyes wide as she looked at abnormally acting Issei who had come into the room, four hours late to the school after being away for days without so much as a notice.

Momonga sighed internally as he waited for the teacher to process the letter's contents.

"A-ah... I see, if it's from Souna-sama..." The teacher coughed and cleared her throat. "Ahem, um, class, it seems that Issei-san will be re-joining us with a different name. He is suffering from a long-term amnesia that is unlikely to go away, which is the reason he has not been present for the past few days, and he has changed his name due to the same circumstances."

"That is correct, teacher-sama." Momonga agreed with a small nod towards the class. "I have, unfortunately, lost most of my personality-tied memories such as memories of names, places, people, and events. However I retain most of my academic skills. That being said, as I no longer feel myself being 'Issei', and I've changed my name to 'Momon'. Furthermore, I've been adopted by the Phenix family due to personal circumstances. This, in turn, makes my new full name 'Momon Phenix'."

He then turned towards the stunned teacher, gave her a small bow, then turned towards his new, and utterly frozen, classmates and gave another small bow. "I hope we all get along, and can start with a new page. It is said that sins of the father are paid by the son, yet I ask that you see me not as Issei, but as what came after, Momon."

A second thought came to Momonga's head. "Hm, could someone direct me to my previous seat?"

A nearly bald boy pointed at an unoccupied seat between himself and another boy, both boys being seemingly in state of shock after hearing 'Momon's introduction. "Ah, thank you, mister..."

"D-do you really not remember?! It's me, Matsuda! Your best friend!" The boy, Matsuda cried, making Momonga pause for a second. 'Hm... I think I should have transferred classes... breaking all the pre-existing relations with Issei might distract me...'

"Wha... wha..." The second boy stammered, taken aback by Momonga's restrained and official behaviour. "I'm... Motohama! You couldn't have forgotten about us! You are just fooling around with not remembering us and trying to get girls to relax their guard so you can take all sorts of pictures? Please, please tell me that's the case!"

"Ah..." Momonga sighed as 'Issei's past was paid for by his mental health. "Fortunately, that is not the case. I am uninterested in peeping on girls. Moreover it would be disrespectful towards my wife."

"W-wait, Issei, a-are those hickeys in your neck?" Matsuda looked as if something had stabbed his heart as he spotted something, and Momonga noticed that the collar of his school uniform had slipped at some point.