Yakuza: Like a Dragon

Nanaba joins your party in chapter 3.
 
You can strengthen bonds with characters by doing activities with them or by fighting with them in your party. The max bond level for all characters is 5, and you can check the bond status by checking the party tab in the pause menu. When a character is missing 20 points, you will not be able to gain any more bond points for them. To move to the next rank, you have to go to Survive Bar and talk to them to advance their personal story. Once you speak to them, you will automatically receive the 20 points and move to the next rank. Repeat this for levels 2-5 in order to max them out. This can be done easily if you have money to blow. Going to the hostess clubs like Lin Lin or Rose Blossom allows you to get massive amounts of bond points. If you max out the happiness meter for the hostesses you pick, you will gain a lot of affection for the party members you bring with you.  You can repeat this consecutive times for fast bond gains. Be aware that you only bond with Eri through the business management minigame, so do not bother doing any activities with her unless you just want to see dialogue.