5 offerings
After 5 offerings the goddess will thank you for coming often. Then she will give you a power berry.
10 offerings
After 10 offerings the goddess will thank you and ask if you had a sweetheart. Say yes and the girl that likes you most will say she's taking a bath. Go in the hot spring and come out and the girl will be shocked your there. Ann's scene is the funniest.
20 offerings
After 20 offerings the goddess will thank you. Then she gives you a piece of wood. Then gotz will show up and buy the wood for 1000G and you will be better friends.