These dramas aren't necessarily similar, but I do think those who enjoy DBS will enjoy Camellia blooms too. There's the dorky male lead romance paired with thriller just like in DBS.

Although Do Bong Soon is definitely the better drama IMO, I think Abyss would be enjoyable if you really liked the romance paired with thriller combo in Do Bong Soon. There is also the same female lead (Park Bo Young) as a plus.