If you make her a meat dish, I believe she gets a buff to the affection actions HilmFrosty described.
kaelic35
Recent community posts
I think you are talking about recipes for the "prepare a meat dish" mission. There's a few of them that I've found.
1. 1 Large beast meat: Hamburger steak
2. Any beast meat + potato: meat skewers
3. Any beast meat + carrot + potato: Beef stew
4. 3 small beast meat: some kind of steak thing
5. 3 large beast meat: steak ball type things.
These recipes give her the happy buff as well, increasing her experience for a red heart when actions are done.
I believe after completing the "don't get hurt" mission for 30 days you get a ticket allowing for an ecchi action. Haven't gotten that far yet though.
I'm not sure what sage mode is, but you level up the heart bar by first building her trust - giving milk, skinship, and chatting (gives red heart). Then, once you have a full red heart, you increase her lust to 100%, turning it into a fully leveled purple heart.
More hearts = more events, choices, and relationship progression.
You can also buff trust gains by cooking imouto a meat dish.
Edit: Remove sage mode by equipping Girl's Smile (Received by finishing second promise).