Both Sirius and The Bridal Mask have in common misunderstandings/ignorance between two brothers and this ignorance leads to regrettable consequences in both of them. However, viewers will also find deep, unbreakable bonds between the brothers in both dramas too... It's fairly hard to explain. They're both exceptionally well made, so watch them ._.
[Spoiler] The third episode of this drama and Sirius are sharing the same theme, all about drugs, also again with the presence of Seo Jun Yeong in both of the two, with an excellent representation of handsome Seo Jun Yeong, you can see how he can play an evil character as his excellent performance in Sirius!
These dramas really remind me a lot of each other. Since they're both about brothers you can expect bromance and bother conflicts from both of them. These dramas also fall under the mystery and thriller genres, though the mystery in Fallen Angel is supernatural while the mystery in Sirius is more realistic. And they have little to no romantic plot or subplot.