It's not too similar but i kind of get the psycho vibe of both jin and jaemin being like "im the only one that can have him and stuff" but i think from how far i am in secret love its more toned down than secret relationships but they are both amazing BL's in my opinion (edit: it gets past the possessive bit fast but they are both still a bit similar)
in both these series its like the bottom likes the top and the top likes the bottom but the top does something messed up to make the bottom hate them for a while ,in both these series i find that the bottom is stubborn and doesn't forgive the top for a while and overall they just give of the same vibe for me (sorry for calling them top and bottom and any spelling mistakes).
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