User blog comment:B214/Volume 23 discussion blog/@comment-1884090-20170413184709/@comment-10330822-20170414191817

Samael, Lucifer, Beelzebub, and Satan are all names for "the devil". In short, they are all the same people. However, this story makes a differentiation based on Dante's Inferno, explaining that they are different people.

In the original story, God made Lilith for Adam to be his wife, but Lilith would not be submissive to Adam, in other words, she was too independent. Adam shunned her and God made Eve for Adam instead.

Lilith was cast out of Eden and was found by Lucifer, who made her his wife and mother to the devils of Hell. Except, in the real story, she just seems to be the mother to Lucifer's children, his bloodline, which consists of Rizevim and Vali. What was interesting is that Rizevim is a pureblood, which means Lucifer made Lilith a demon at some point.

Now, Samael was the temptor of Eve to eat the Fruits of Knowledge of Good and Evil. The original sin. What we are kind of suggeting is that Samael did more than just "tempt" Eve. Either way, Samael was cursed by God for his actions and became what we see him as in DxD.