If you want to sound old fashioned and a little bit fancy, you can refer to your boyfriend as your swain.
A servant.
Noun
a man who is the lover of a girl or young woman; "if I''d known he was her boyfriend I wouldn''t have asked"
n.
A servant.
n.
A young man dwelling in the country; a rustic; esp., a
cuntry gallant or lover; -- chiefly in poetry.
Swain
Him behoves serve himself that has no swain.2.
It were a happy life To be no better than a homely swain.
Blest swains! whose nymphs in every grace excel.
A servant.
Usage Examples
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