The couple from Happy & Love Forever play a supporting part in the first episode of Sunny Happiness. Also, its your basic romantic comedy too!
Happy & Love Forever (2010)
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They are both part of the same trilogy . Similar vibes very different storylines. SH has a more melodrama feel. The main leads in H&LF are in the opening episode of SH on their honeymoon.
In both dramas, two best friends fall in love. Also, Annie Chen stars in both.
Same lead actress, same story of strangers engaged by force/circumstances, same vibe. The dudes make all the difference.