Super Sentai / Power Rangers
"Finally, the prophecy has been fulfilled. The sixth ranger is now one of us."
—Zordon, Mighty Morphin' Power Rangers
"You're a Gokaiger...our sixth member!"
—Captain Marvelous to Gai, Kaizoku Sentai Gokaiger
"Aw, come on! Now there's six of you?!"
— A very unfortunate Monster of the Week, Power Rangers Samurai
"You've truly become the sixth ranger."
— Troy to Robo Knight, Power Rangers Megaforce
Other series
But when I look around I see
That someone is smiling back at me, wait!
There's someone talking to me
Gee, I've got a new friend
— Degrassi Junior High theme song
I didn't expect a third Pretty Cure...
— Gentlu, Delicious Party♡Pretty Cure
Another shipmate? Yes, the more the merrier!
—Announcer, Galaxy Quest
Finally Found! The Third Pretty Cure!
— Episode title from HeartCatch Pretty Cure!; ironically, it's about the wrong person
Jake: Five kids against an enemy that has destroyed half a galaxy? Five of us?
Ax: (smiling) <Six, my prince.>
Marco: Six. Well then, with six it shouldn't be any problem.
Ax: (smiling) <Six, my prince.>
Marco: Six. Well then, with six it shouldn't be any problem.
— Animorphs, "The Message"
"And when they're with Daizy, the fun never ends!"
— Wow! Wow! Wubbzy! theme song
Max: You don't want me in your party?
Mike: Correct.
Max: Why not?
Mike: Because you're annoying! Also, we don't need another party member. I'm our paladin, Will's our cleric, Dustin's our bard, Lucas is our ranger, and El's our mage.
Max: Well, I could be your zoomer.
Mike: That's not even a real thing...
Max: It could be!
Mike: Correct.
Max: Why not?
Mike: Because you're annoying! Also, we don't need another party member. I'm our paladin, Will's our cleric, Dustin's our bard, Lucas is our ranger, and El's our mage.
Max: Well, I could be your zoomer.
Mike: That's not even a real thing...
Max: It could be!
—Stranger Things, "The Pollywog"
"Despite not fitting in with that main cast, he shows up out of nowhere and abruptly wins the episode's battle because he's unbalanced and OP. You could say he's a reliable trump card, but on the other hand, that's exactly why he doesn't fit in."
— Kirito (explaining why Shirou is called "the Sixth Ranger"), Fate Revelation Online