In order to get their heart level to full,save a sandwich everyday for Pharaoh.Give it to said cat,so he will start following you.Talk to your partner-to-be.If they blush when you choose Duels,Hobbies,or The Academy to talk about,then you will gain some trust.Give them sandwiches,everyone has different tastes,but lucky for you,I know 'em.If you have great luck in drawing the Golden Eggwich,good for you,since they love it.Duel them every day,also,when they begin to mail you about meetings,that means you've gained some trust.
Jaden-eats anything,especially the Golden Eggwich and Destiny Sandwich.He uses Elemental Heroes,and often uses good Trap cards,so I suggest that you choose monsters that are unaffected by Trap cards.Also,he often uses Fusion monsters,so choose Continuous Spell cards that doesn't allow either player to Fusion Summon.
Alexis-loves sweet foods,but dislikes anything that smells,like the Durian Sandwich.She uses Warrior-Type monsters,like D.D Warrior Lady.But some of them aren't really strong that much,so if you immediately see a monster that increases the attack of all Warrior-Type monsters on the field,destroy it immediately!
Chazz-he sticks to the Ojama Trio and his Dragons,so if you see a face-down monster,destroy it,it may be Armed Dragon Lvl 3 or Ojama Black,Yellow,or Green,also,if you notice he only Sets a monster,that marks that you have to destroy it,unless you want a taste of his Armed Dragon Lvl 5 or Armed Dragon Lvl 7.He likes the Lobster Sandwich,bit dislikes vegetables.
Bastion-he likes healthy foods.He has a lot of decks,so its really hard to figure it out once in a while.He dislikes fruit and sweets, 'kay?
Zane-he likes the Plain Sandwich.He mainly focuses on Spell Cards that destroy face-down monsters,so you should not Set monsters too often.For more information,check out his deck at yugioh.wikia.com/Zane_Truesdale and check out his decks in the Yugioh GX Tag Force.
Syrus-loves the Lobster and Fried Shrimp sandwich.He uses Vehicroids,so destroy his monsters immediately,unless you don't want to get beaten up by his monster with a 3000 attack.Seriously,dude.
Chumley-eats about anything,except the Dried Sardine Sandwich.He also depends much on Fusion,so,use the cards that doesn't allow either player to Fusion Summon.He loves the Salmon or Mackerel sandwich.