Next to nothing is none of Gowther's past. After the exile of the Seven Deadly Sins Gowther traveled to the Ordan Forest in a attempt to hide. There he encountered a crazed monster with evil power so he sealed it inside his armor. Later Gowther is found by young boy and is seemingly injured very badly so the young boy takes him into the village to help him.
Gowther has dark red hair and amber eyes. His casual clothes outside his armor consists of a long-sleeved grey shirt underneath a white sleeveless top, along with a pair of boots and pants. He also wears glasses with light frames and is virtually blind without them. Gowther has a very feminine face and was only recognized by his voice at first when the Seven Deadly Sins found him. He can also seemingly change his appearance to extent. When he was found by the young boy Gowther made his hair longer to represent the boys deceased mother and shorter to fit in with the kids.
Gowther is depicted as a emotionless person. His face always stays the same never changing during even intense battles. Though he appears to carry no emotion he does care for others as show when he protects Pelio the young boy who saved him from the Armored Giant sealed inside his armor. Often times he seems unaware of others emotions and has no regard for privacy as shown when he tells everyone how Elizabeth is in love with Meliodas. Despite being the Goat's Sin of Lust he hasn't shown any attributes associated with the name and has actually shown a rather cruel side when using his Nightmare Terror technique on a Holy Knight showing his deepest fears with no remorse.
When rescued by the young boy Pelio, Gowther disguised himself as Armando a fake character he made to hide his true identity so he wouldn't attract Holy Knights. As Armando he displays a attitude more associated with his sin title and acts flirtatious and fluttered at times.
Gowther is first seen disguised as Armando playing with a group of young children from the village he is staying at. While playing and adventuring with the children they stumble upon the Boar Hat bar with Pelio demanding that Meliodas to show himself and questions him as to why they built the bar in the village without his permission. After a initial misunderstanding the children of the group end up liking Diane a lot and play with her while Armando talks with Ban apologizing for the trouble his friends may have caused. Ban warns him that playing as the Seven Deadly Sins is a bad idea because they could anger Holy Knights. Immediately after Ba warms him they hear a roar coming from the forest.
Armando tries to warn Pelio not to go to the forest as it is very dangerous since a townsman from earlier said that the Holy Knights were hunting a dangerous criminal. Pelio blows off his warning just marking Armando as a coward and continues on.