During or after Chapter 7, select Leanne and look at the wardrobe in her room. Enter one of the following codes when she says "Hmm, I think that outfit is in here...", then press A to advance to the next line of dialogue and unlock the corresponding costume.

Costume	How to unlock
8-bit Girl	Press Down(2), Up(2), Left, Right, Left, Right, Y, X.
Club Famitsu	Press Y(2), Up(2), X(2), Left(2), LB, RB.
Gemaga	Press RT, LT, LB, RB, Y(3), X(2), Up.
Hirakou	Press X, Y, LB(2), RB(2), click Left Analog-stick, press Up, Down.
Platform Logo	Press Left, Up, Right, Down, RB(2), LB(2), click Left Analog-stick.
Politan Suit	Click Right Analog-stick(3), press Right, Left, Y, X, LT, RT, LB. Note: Earn the Reindeer Suit in Neverland first.

Chapter 6 or later required Combat Scope Betas cost 3000 gold, one glass shard, and one scrap of iron to make. The wandering merchant sells glass shards and iron scraps for 200 and 150 gold respectively. Combat Scope Betas sell for 4100. Profit is 750 per scope, multiplied by 999, is 749250. The best time to do this is chapter 6~7, before the merchant starts wandering she is always at the Waterless Bridge. In chapter 8 plus, she can be at Forsaken, the Waterless Bridge, or the Righteous Tower. Your best bet then is to get into an enemy counter, run away, and check the location to see if she is there. Time phase changes also change her position. Repeat as necessary.

Successfully complete the game. You can start another session on your saved game file. Additionally, in Chapter 2, you can enter ReanBell's (Leanne's) bedroom and press [Action] at her wardrobe to activate a secret button. It will allow Reanbell to remain in her current costume instead of changing into the pig T-shirt in the cinematic.

In Chapter two of a new game +, go into ReanBell's (Leanne) bedroom and press x at her wardrobe. There is a secret button which when pressed, will allow you to keep Reanbell in her current costume rather than going into the pig t-shirt in the cutscene.

During or after Chapter 7, select Leanne and look at the wardrobe in her room. Enter one of the following codes when she says "Hmm, I think that outfit is in here...", then press X to advance to the next line of dialogue and unlock the corresponding costume.

Politan Suit: Press R3(3), Right, Left, Y, X, LT, RT, LB. Note: Earn the Reindeer Suit in Neverland first.
Gemaga shirt: Press RT, LT, LB, RB, Y(3), X(2), Up.
Platform Logo shirt: Press RT, RB, R3, L3, LB, LT, Right, Left, X, Y.
8-bit Girl shirt: Press Up(2), Down(2), Left, Right, Left, Right, Y, X.
Hirakou shirt: Press X, Y, LB(2), RB(2), L3(2), Up, Down.
Club Famitsu shirt: Press Y(2), Up(2), X(2), Left(2), LB, RB.

In Chapter 14, when you head to the dungeon to fight the boss, nothing seems to happen. Run through the bottom section, go back to the dungeon map and run around to the top entrance. Go all the way south through the dungeon again and there will be a switch sitting in the corner, look for it and flip it. When you flip it a gate opens allowing you to return to the initial area. Go all the way southeast (backtracking through previous areas) and the boss will appear.

In Chapter 6 or later, the Combat Scope Betas cost 3,000 gold, one glass shard, and one scrap of iron to make. The wandering merchant sells glass shards for 200 gold and iron scraps for 150 gold. Combat Scope Betas sell for 4,100 gold. Thus, you will make a profit of 750 gold per scope. The best time to do this is chapter 6-7, before the merchant starts wandering she is always at the Waterless Bridge. In Chapter 8+, she can be at Forsaken, the Waterless Bridge, or the Righteous Tower. It is recommended to get into an enemy counter, run away, and check the location to see if she is there. Time phase changes also alter her position. Repeat this trick as many times as desired.

In Chapter two of a new game +, go into ReanBell's (Leanne) bedroom and press x at her wardrobe. There is a secret button which when pressed, will allow you to keep Reanbell in her current costume rather than going into the pig t-shirt in the cutscene.

Beat the game and you'll be able to start a new game with some of your items and skills intact. When you do this, you can change your costume in Leanne's bedroom. Approach her wardrobe and press the action button.