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In love and war, there are no rules.
Literal
Romantic-love [and-と] battle [topic-は] road [object-を] do-not-choose.
A variant of the 'love and war' proverb that swaps 手段 ('means') for 道 ('road, way'). 道を選ばず = 'does not choose (one's) road' — carries the same 'anything goes' meaning, with 道 adding a more metaphorical 'path of action' flavor.