We've all known that Prince Harry is dating Cressida Bonas (whose style is the complete opposite of Kate Middleton's), but there haven't been any official announcements about their relationship. Well, we're definitely taking steps in the right direction, because Cressida joined Harry at one of his official engagements today -- for the first time! (Um, this is big in the royal world...)

Wearing dark skinny jeans, a leather-trimmed jacket and sparkly converse sneakers, Cressida continued her casual-cool vibe as she supported her boyfriend. Some call her the "anti-Kate," since their style is SO different, but we love it! She seems perfect for laid-back Harry. Plus, if Cressy is about to become an addition to the royal family... she's sure to mix things up. We expect a little royal "polishing" might take place, but hopefully she keeps her own unique style!

Harry was speaking at a WE Day UK youth event -- the goal of which is to empower children to create social change. He spoke to over 12,000 students and teachers, joking "For those of you who were expecting Harry Styles here, I apologize, and no, I am not going to sing." Cressida sat in the crowd with her half-sister Isabella, brother-in-law and Harry's cousin Princess Beatrice.

"Some people do not think it is cool to help others," Harry said at today's event, "personally I think it is the coolest thing in the world." Princess Diana would be proud.

Click through the gallery above to see more photos of Cressida and Harry from today's event!