RPG Insanity

So i have found the ending requirements in this game is unique.Unlike the other Asdivine's games,the normal ending still available even after the post-game.Also there are two optional ending depending on what weapon you're used.The game's plot will also changed.
"I'm going to head home!" = Don't use Arondight sword.Instead use other weapon.
"I'll think about it after i get home!" = Use the Arondight sword.

-Character normal ending-
"I'll go to Lightoria kingdom!"~Celes normal ending~ = Celes trust level 100%

"I'll go to Zandark kingdom!"~Nisha normal ending~ = Nisha trust level 100%

"I'll travel the world!"~Akane normal ending~ = Akane trust level 100%

Meanwhile the true end only available after post-game.

"I'll stay with Celes!"~Celes true ending~ = After post-game.Celes trust level 100%

"I'll stay with Nisha!"~Nisha true ending~ = After post-game.Nisha trust level 100%

"I'll stay with Akane!"~Akane true ending~ = After post-game.Akane trust level 100%

However i haven't found the harem/happy end yet.I'll start on the post game content first.

How do you start the post-game? I defeated Tartarus both with and without using Arondight, and nothing else unlocked.

In order to unlock the heroines true ending you must save the game,load the game again and get their trust level 100%

Equipping the arondight just to make certain ending.

Equip arondight->get Axel and Feena ending
Not equipping ->get ending the death of Axel

In this game there aren't extra main quest and the final boss battle still same so the post-game content are quite less than the other asdivine games.

How do I increase trust levels of the heroines? I haven't found items to give them for that purpose. I mean I don't know how to get such items. I read somewhere that they are in treasure chests and they drop from battles. But what chests and where do I grind for them?

I don't remember where i get them in treasure chest or drop item. However you can exchange for them in shop using spirit stone(not from monster drop) and the only way to get it is using random battle accelerator and grind for it.

> Ancient tome > Akane trust +5
> Cosmos bouquet > Celes trust +5
> Teddy bear > Nisha trust +5
> Squid biscuit > Anyone trust -10
> Special gift > Anyone trust + 20