Okay but pre Kerberos Sheith weren’t dating or fucking or anything. They were just friends? Like that much is obvious.
Let’s take a loot at the dialog in episode 1. This is what Lance calls Shiro. “Senior officer” now depending on the area a senior officer can be different things (there’s different types of senior officers like for prisons, royalty, etc), typically in the army they’re like a lieutenant who serves under a commander. Shiro is called that because he graduated top of his class as a pilot. That’s all that he was for the Kerberos Mission, a pilot & nothing more. Sam Holt was the Commander of the mission, he was the leader, a teacher.
Now in episode 1 This is what Lance calls Iverson their teacher:
He calls him Commander Iverson, a commander holds a position of authority over troops, or cadets. He’s the teacher.
This is what Hunk calls Montgomery, another Commander/Teacher:
“Professor” was used. Indicating some kind of teacher.
Now we know Lance calls Shiro his hero, meaning that Lance knew about Shiro preKerberos. Lance calls Shiro “the pilot of Kerberos mission.”
He doesn’t call him commander or professor, or some formal title like that, he just calls him “the pilot of Kerberos.” You would think that he’d call Shiro commander or professor if he’d been a teach In the past, but Shiro was just a high ranked pilot serving under Commanders.
Okay remember the scenario in episode 1 where Shiro is about to be sedated by Iverson & his staff & lance says “The guys a legend, they’re not even gonna listen to him?”
He doesn’t say “that guys a commander or professor just like them? Why don’t they listen to him?” He just says “that guys a legend”. Meaning there was no authority to his name that Shiro could have used to help him, he was just a really good pilot.
Hunk doesn’t use titles like commander or professor for Shiro, neither does Keith, neither does Pidge. Keith was able to be close to Shiro because they were both students. Pidge, who probably heard and knows a lot about Shiro through Matt doesn’t address him as Commander either, even though she would technically know he was a teacher or something of authority figure.
That being said, I still believe Shiro to be a student, or just a high ranking pilot at the Garrison, not some kind of teacher or professor.