From Wiktionary, the free dictionary
From romantic + -ity.
romanticity (uncountable)
- The state or condition when romantic feelings are felt or conveyed.
2012, Martha Read, Richard S. Pressman, Margaretta[1]:[…] she, all unconscious of her power, endeavored to pass unheeded, and he with all the romanticity of love, bowed observance to her mandates.