gdgd Men's Party

In the series, Light and Yomi are spending their daily lives happily playing video games. One night when everyone else is asleep, Light receives an invitation from Alpha, a messenger for someone named King. Light and Yomi are then sucked into another world, where they must undertake a quest to rescue Princess Melody from the demon lord. Light thinks this must be his destiny, while Yomi thinks it's kind of annoying. They form a party with Alpha to start their quest. Alpha as it turns out is an AI robot, and he has a program that allows them to raise their levels while slowly continuing their adventure.

(Source: ANN)