look up any word, like tribbing:
 
1.
The 121 rule is the girl code for not getting back with an ex. The girl had 1 to 1 attention of his but for whatever reason they split up. Whether the girl likes the ex or not , the fact remains that she just not going down that path again. The 121 rule usually refers to a heterosexual relationship but that doesn't mean a gay or lesbian person couldn't follow this rule.
girl 1: "Omg you should so get back with him, you too we're so cute together"

girl 2; "No way. I follow the 121 rule!"

girl 1: "Ahh, I see, It's a shame though"
by wildcardchic March 16, 2014