1: If I buy a premium background for a certain wolf (let's use the Waterfall as an example) and change it to another background afterwards (accidentally or for whatever reason) and I'd like that premium background back for said wolf.

Do I have to buy the Waterfall again? Or will it be accessible for that certain wolf forever for free?

2: How does Make Friends increase the affinity of a wolf with the pack? If I have an Bad Affinity wolf for example and use Make Friends on them, will they become OK? Good? Or Excellent?

Thanks for the replies in advance!

2- If the level upgrades that improves the affinity, example, my wolf Polaris had Ok affinity but he upgraded his level and got Good affinity

I've used one on a wolf with 'Ok' affinity and her updated affinity was 'Excellent.'

I'm not sure as I've only used it once.