Headcanon that Jonathan doesn't like to be called Jon or Jonnie because it's too close to Lonnie. It's either Jonathan or nothing. . .he didn't realize there was another option until Steve called him Nate.
"Why?" Jonathan would blurt out.
"Yeah, it would be cute, don't you think? Nate and Nancy?" Steve said and smiled a crooked smile.
Steve stared at him with his wide, very expressive eyes, and Jonathan stared back for a moment. He turned on his heel and walked back to Nancy.
"Uh, yeah, you don't have to worry about choosing one of us, I think I'm in love with Steve, too," Jonathan said.
"What?!" Nancy asked.
"Also, I will accept Nate as a nickname," Jonathan said.