This is a crossover between UnderSwap(If you don't know what that is, it's a Alter Universe of UnderTale if you play undertale you should know about the characters well in underswap the characters are swap for example Papyrus is swap with Sans and Sans has Papyrus personality while Papyrus has Sans personality and powers.) Other AUs of Undertale,Classic Undertale, and Hyperdimension Neptunia it is a Blueberry Sans Male Reader x Harem: It has been years since the human named Chara falled from the surface world and befriend all the monsters then released them into the human world Asgore and Toriel treated her like a daughter also they know about alternative universes because Blueberry Sans or Y/n has been making friends of different Sans and Papyrus even the evil ones like Error Sans and Horror Sans even he befriended every Frisks and Charas when a portal appeared Y/n saw this portal and called his big sister(that's right he is a female and in a harem if you have a problem with it then don't read this challenge or take it.)

(This is a female underswap papyrus.)
She arrived with Chara and Undyne(underswap version) until the portal started to spin and pulling everyone in it Papyrus, Chara, and Undyne holded their ground but Y/n wasn't lucky he got pulled in the portal his older sister screamed out his name then the portal closed Papyrus went down to her knees and shouted out your name -Meanwhile with you- The portal opened at Gamindustri you felled out of the portal and falling down to the ground with Neptune on top of you until you woke up in a pink room you tried to get out of the bed but you were held down by a girl with pink hair and buttons on her head you looked at her and got confused until you grab your head in pain and started to remember everything about your life then the alarm clock woken the girl up from her sleep and looked everywhere until she locked her eyes at you and blushed.(Oh by the way here is what you look like.)

(Human version of blueberry Sans. Let's continue with the challenge.)
You looked at her and wondered if she is sick but she grabbed your head and place it to her chested you looked up and stared at her eyes she had hearts in her eyes then a girl enter the room and saw that they are awake she introduced herself to be Compa and asked for their names the girl with buttons on her hair said her name is Neptune and you said your name is Y/n causing Neptune to said destined lover Compa heard this and said that Y/n is her destined lover Neptune glared at her while you just sit there and smile because you made friends and you are dense. That's the challenge, Y/n's personality: he's like papyrus. Y/n's harem: All female Sans(expect for underlust and underflesh.), Female underswap Papyrus, Neptune, two Verts(Ultradimension and Hyperdimension), two Noires, two Blancs(Heroesfan10009 and USAGamer178 you are going to love these pictures of Blanc and her Hdd form or hate it.), Uni, Nepgear, Ram, Rom, Aforie, Historie, Rei Ryghts, Compa, Iffy, and the dark cpus. Alright here are the pictures of Blanc and her hdd form(Wattpad wouldn't show you her hdd form.):

Blanc with her huge honkers.

Here is the female Sans pictures:

Classic Sans

Underfell Sans

Horror tale Sans

Ink Sans

Error Sans(my favorite sans out of all other sans.)

Geno Sans
That's it for the sans. Do you accept this challenge. Yes or no?