Wingding Gaster

Little is known about this enigma. Wingding Gaster is the father of both Sans and Papyrus. Gaster worked alongside Alphys to test 'Determination', a human trait that simply didn't exist for monsters. He had tested on yellow flowers and eventually, due to lack of volunteers, he asked his son Sans to eat Determination Pills, containing 3% of a humans soul each. While papyrus eventually did have a Determination Pill, Sans accelerated further and faster. Gaster saw the effects of this and subjected himself to Determination. However, he gave too much too fast to himself and became an abstraction, lost in limbo between existance and nonexistance, everywhere and nowhere, left to suffer forever as his son Sans was forced to grow up faster to raise his younger brother.