>>538803208
https://bluearchive.wiki/wiki/Affection
You have 2 cafe floors and one invite for each, but a student can't be in both floors at the same time, so rotate those invites for each cafe reset (every 12 hours), Invite your wife to one floor in the morning after one reset, and the other floor in the afternoon after the other one. The max you can pat is 8 times per day, most people can do it 6 or 7 times
Normal gifts are worth 20 affection, favorite gifts are worth 60, so you should always craft gift selectors with normal gifts to convert them into favorites, you get 50 yellow stones every month when the drill shop resets so that's 50 crafts per month, plus whatever you can get from set
Crafting to the third node increases the chances for more gifts, and can get you purple gifts which are extremely valuable
Obviously it takes time even with dedication, so be patient