Out of a hundred emails I receive containing questions about Harvest Moon, at least a quarter of these tend to be desperate appeals for help because the player gives gifts that an eligible girl or bachelor loves and yet, his/her AP keeps going back down to zero!
The reason for this, as I have stated again and again in my Guides, is because the Harvest Goddess who watches over the land is very strict with respect to littering. She has taught her people not to throw items recklessly into the roads, into the seas and rivers or anywhere else... In almost every Harvest Moon game, you will find rubbish or trash bins in the Village Square and in your own house. In some Harvest Moon games, you actually can ship rubbish items such as old boots and empty tins to obtain a little extra income. What you MUST NOT DO is throw the items on the ground or into any body of water.
If you 'catch' an old boot with your Fishing Rod, do not throw it back into the water. Take it to the nearest rubbish bin or ship it... or if you are playing a game that features the little girl May, you can give it to her as a gift and she will be thrilled with it. (She is one of the few individuals who actually LIKES rubbish, apart from the Witch Princess in HM DS and Cute who likes some rubbish items but not others. You can give the Witch Princess your empty tins and fishbones, for example.)
In some Harvest Moon games, you can pull weeds on your own land and toss them aside without incurring any penalties but in Harvest Moon DS and Cute DS, throwing even a weed onto your own field is considered littering. The Witch Princess may give you her own gift of rubbish if you toss 10 weeds, but although you have been given that dubious award from her, you will lose AP with eligible bachelors/girls! Do not drop or throw ANY item on the ground or water ANYWHERE in Harvest Moon DS or Cute DS. Affection WILL decrease when you do...
In some games, it is only the affection and/or friendship of individuals within a specific radius that will decrease when you litter. In others, the effect will be general.
It may be useful to add a note here about throwing a small fish into the ocean in order to catch the King Fish. You must do it if you wish to catch the King Fish in question, but it WILL be considered littering and you will lose affection/friendship in every Harvest Moon game when you do it. Make certain to remedy the loss as quickly as possible... that's the best you can do.
In some games, you actually can go to Confession at the local Church and be absolved for the 'sin' of littering. This is worth doing, actually, if you either have dropped an item by accident or have been forced to throw a small fish into the sea to catch the King Fish. Those players who, when trying to give a favourite item to an individual, have dropped it by accident when the intended recipient has moved away suddenly will lose not only the item and the benefit of the gift but be punished with a littering penalty! We've all experienced this, I expect... I usually reload in such cases, even if I am forced to relive an entire morning...