Quiero llenarte de leche mami.
Now if you want a creampie - quiero dejarte preñada (make you prego) mami.
“Quiero llenarte de leche mami” is the best option to go with
“Quiero dejarte preñada mami” is more like saying to a woman you want to cum inside her and have your babies lol
I’m Salvi but if I didn’t know Spanish better I would Say “Mamada profunda” for deepthroat and make the hand and head gesture
Cum inside you I Would say “quiero venirme adentro de ti”