Hey, Miroslav is really pretty! :) Especially because it's Slovakian, it makes me think of Vlad Dracula then, because he lived in Transsylvania (= nowadays Romania) and that's a country close to Slovakia. :)
But I was wondering... from what I can tell from all that you wrote, both you and your girlfriend/wife practice satanism, so that means you believe in Satan and that you are against God and all.... then why take a Christian name as a second name?
Anyway, you know what's also cool? Latin names as a second name. Latin is a very ancient language and thus Latin names sound a bit mysterious and dark, some may sound even evil, maybe. ;) So, that might also be a good idea for a second name (or for a first name, depends on what you like). I'll give you a few examples of male Latin names....
Aegidius Aemilius Alexius Aloysius Anastasius Antonius Arcadius Asterius Augustinus Aurelius Aureolus Basilius Benedictus Caecilius Carsilius Cassius Christophorus Diocletianus Dionsius Dominicus Emericus Florianus Franciscus Gerardus Henricus Hieronymus Johannes Josephus Julianus Julius Justus Laurentius Lucius Marcus Martinus Mauricius Maximus Mercurius Nicasius Nymphidius Olympius Philippus Quartinus Quirinus Requiem Romulus Rothericus Saturnus Severus Sirius Theodorus Tiberius Timotheus Uranius Victorius Vitellius Wilhelmus Zacharius