REUTERS - Sep 24 - Cupid PLC was hit by higher marketing and administrative costs. Adjusted pretax loss for the six months ended June 30 was £2.5M ($4M), from a profit of £3.5M a year earlier. Revenue rose 12.4% to £43.4M. Marketing spend increased 18% to £27.4M. Administrative expenses rose ~60% to £4M. Cupid said it expects continuing business to return to growth and profitability in 2014.