The romance was pretty good. The ML and FL had solid chemistry, but the ML's tragic story and his portrayal of it carried most of the show and took over / overwhelmed the romance.
However, the real star of this drama was the bromance between the two male leads. Their friendship and their scenes (and their friendship chemistry) stole the show. I ended up fast forwarding all scenes just to get to the friendship side story.
Of note, the overall plot is a little convoluted, but-- like I said-- the friendship plot completely charmed and made up for (mostly) the other deficiencies. Not that you asked, but I didn't care about or have a favorite of the two potential love interests for the friend male lead and, other than enriching his character, that part fell flat (for me).