pls help me find this

i read this one manga that was about this girl trying to avoid marrying, so she went to this masquerade party where you find partners for the night. then some witchcraft happens and she ended up sleeping with the dude she tried to avoid getting married to. anyways big ol haha i bet my seeds still in, youre probably pregnant rn and thats when she pulled that reverse haha and said she used contraception. big surprise because it turns out that the shop witch(?) was trying to stay hidden and the dude who i think was the prince has been trying to get contraceptives or horni begone medicine. something like that, i lost it and i stayed up looking for it, pls help me