Devil Union 

Devil Union is a special transformation available to devil hosts who have undergone the Devil-Binding Ritual.

The host draws on the full power of their devil and assimilates the devil into their body, enabling them to contain and control the power of the devil and dramatically increasing their own magic power and capabilities. The host takes on physical traits of their devil, such as horns, a tail, and slit pupils, as well as being garbed in their devil's power.

Asta: Liebe let's go.... DEVIL UNION!!!

Devil Union by Storfy June 11, 2021

Devilution 

An evolution of an evening whereby events spiral to a level where good people do bad things, usually regretted the next day, and generally inspired by one person being the group devil who likes to reak havoc.

There is a random probability that an evening ends this way, 50/50 usually determined on a toss of a coin or which way the wind blows.

Therefore Devilution is the random probability of good being evil and evil being good. Usually determined by a toss of a coin or which way the wind blows.

In a world where there are only two kinds of people, Devils and Saints a classic devilution of an evening is a Saint behaving like a Devil or vice versa. More than likely there is alcohol involved and events can be more pronounced on evenings such as Rapture where the pending end of the world determines the coin toss, on nights such as this there is a direct correlation between devilution and apocalyptic sex.
There is always a 50/50 chance of a Devilution not occurring, this ratio is determined by the toss of a coin.
When one wakes the next day they use hopium to convince themselves they haven't done anything bad.
Events are more pronounced if there is a hotness hypnosis situation occurring between two parties.

Devilution by Devil72 October 31, 2011