noun
post-Valentine's blues (for men who received no chocolate)
Slang term for the depressed feeling some men experience after not receiving Valentine's Day chocolate. Often used humorously or self-deprecatingly.
今年もチョコをもらえなくて、二月病になりそうだ。
I didn't get any chocolate again this year, so I think I'm coming down with the February blues.
Compound of 二月 (February) and 病 (illness), modeled after terms like 五月病 (May blues). The exact origin is uncertain, but it likely arose as a humorous slang coinage.