culture
A 21st-century online buzzword popularized by fan communities discussing TV dramas, BL/danmei fiction, and sports rivalries. Despite its symmetrical four-character form it is not a classical chengyu - pre-2010 dictionaries don't list it. Now mainstream enough to appear in news headlines.
usage
Applies broadly: romantic couples, frenemies, business rivals, even nations (中美相爱相杀, the US-China love-hate dynamic). The tone is half-tongue-in-cheek; using it about a real bitter conflict can sound flippant.
