Learn English – a word for a relationship where one party benefits while the other gains/loses nothing

I'm a programmer and I need a name for this relationship. A bit more elaborate description:

I have a banana, a pear and a pineapple in my lap, they all taste equally good. If I add an apple to them though, suddenly the pear tastes 3 times better, while there is no effect from the pear to the apple or between any other fruit for that matter.

It cannot be symbiotic since that would require mutual benefits.

It cannot be parasitic since the apple isn't losing anything despite helping out the pear.

I don't think its synergetic since the whole advantage of adding an apple to the configuration is given to the pear and even though the taste quality of the fruit pile is increased, the quality of the whole is not important and therefore cannot be perceived as beneficial.

I'm not sure about empowering since it feels like the apple should be willingly giving something away.

Any other words you can think of?