Change your main character’s affinities ASAP

Another cool feature of Essences is that you can use them to change your protagonist’s weaknesses and resistances. This does require the “Divine Amalgamation” Miracle, but you’ll fortunately gain access to this early in the game. By selecting “Essence Fusion’’ and then “Affinities,” after selecting your protagonist in the World of Shadows, you can select which monster’s defenses you’d wish the Nahobino to mirror. You’ll want to do this as soon as you find a suitable Essence, as by default, your Protagonist has a dangerous weakness to Mudo.
For those new to Shin Megami Tensei games, Hama and Mudo (the Light and Darkness elements, respectively) have unique properties. Not only do these elements inflict damage in Shin Megami Tensei V, they can instantly KO anyone who is weak to them. Considering that you’ll instantly get a Game Over if your protagonist loses all his health, sticking him with a perpetual Mudo weakness is courting disaster. All it takes is one unlucky battle where the enemies attack first and you’ll immediately lose all your progress without recourse.
For the early game, Cait Sith and Halphas are mostly neutral Essences that should keep your protagonist from becoming a liability. Unicorn and Apsaras are also helpful, as they pack resistances to the Charm status effect as well. We’ll get back to why this is important later.