You were an experiment. One of W.D Gaster determation experiments. But you were a failed experiment. Sometimes you would be strong enough to fight. Other you could barely move. Your HP dropped fast in battles. Once you reached 0 HP you started melting. But more determation always fixed that.

So this wouldn't happen all the time you were made a monster human hybrid  (if you have read my Sans X Reader I'm just going to point out something in this you are a hybrid not The Hybrid) you had cat ears, wolf tail, bird wings, whiskers and gray skin.

Then there was Gaster assistent, Sans.You had a crush on him. He talked to you most of the time. Gaster didn't like it at all. He didn't want anyone getting close to you in case on day something went wrong and you died.

Tonight was like any normal night. Gaster would leave, Sans would check on you before leaving. You had fallen asleep early today and hadn't heard Gaster leave. You awake suddenly from a nightmare falling off the bed.

Sans who was sitting in the chair next to you woke up when you fell on him. "Uh.. hi" you felt your face heat up. Sans was also blushing. You sat in silence "bad dream?" Sans asked. You noded "yeah"

Sans put his arms around you and held you close. You closed your eyes but didn't fall asleep. "I love you" Sans whispered.

Those three words.

Those eight letter.

You had wanted to tell Sans for ages and he had just said them to you. You took a deep breath in "I love you too"

***Bouns***

Gaster had found you asleep with Sans. He wasn't at all happy with it. He had banned Sans from seeing you. Sans still promised that he'd come and see you each night.

That one promise filled you with hope. You got better at fighting. You no longer melted when you HP got to low. It started rising at times. At first Gaster thought you were killing monsters. But when you LV stayed at zero the same he didn't know what to think of it.

It no longer was determation that kept you going it was hope.

Next up reaper sans X dying! reader

Later mafia sans X reader

Then Gaster X monster! reader