Persona 5 has a variety of friends to make, from a board game pro to a moonlighting teacher and a failed politician. There are some pretty fantastic benefits to pulling on those threads, but it's also really important to hang out with the kids who actually fight demons alongside you. Ryuji Sakamoto is the first one you unlock and is one of the easiest to max out.
Persona 5 Ryuji confidant: Maxing out the Chariot Arcana social link
You'll automatically become friends with Ryuji early in the game's story, whether you like the somewhat annoying troublemaker or not. Since it's a while before you get enough party members to justify leaving him out of combat, it's worth your time to hang out with him and rank up for the valuable benefits.
GamersHeroes has a comprehensive guide if you want to know the best responses in every conversation with Ryuji, but it's not like there's a way to fail the social link. All you have to do is hang out with him whenever he asks (and whenever you have time) and it'll get to rank 10 eventually. Bring along a Persona of the Chariot Arcana (Slime is a good one to find early on) to speed up the process.
At one point in the confidant friendship, Ryuji will stand in the school hallway for a while and, when prompted, will refuse to hang out with you because he needs to find out a particular character's drinking schedule for sleuthing purposes. This can be confusing and a bit frustrating, but you haven't done anything wrong. Just wait a while and finish whatever palace it is you're infiltrating and, eventually, Ryuji will contact you in the evening to let you know that he's ready to continue.
Stay diligent in hanging out with him, and you'll eventually get to 10 with Ryuji. His Persona will evolve, and you'll be able to fuse the most powerful Chariot Personas possible. I know Ryuji is not the best character in the world, but give him a chance.
More Persona 5 news, updates, tips and tricks
For more on the latest entry in the Persona series, check out the rest of what Mic has to offer. Here's a guide to building relationships with the game's Confidant system, and a guide to when and how you can name your main character.