Well, I wanna share something about one of my favorite ships from IE. It won't surprise people who know me but...
Endou Mamoru/Kazemaru Ichirouta (Or Mark Evans/Nathan Swift for my French fellas), everyone. I mean...
First, they're childhood friends. They have known each other from a young age! They grew up together, they probably went to the same elementary school! It means that they built a solid bound overtime, with trust towards each other.
Second, Kazemaru/Nathan would do ANYTHING to protect his friend. Even taking powerful shots in the head! What a hero! That's what I like about him and Endou/Mark. The first one is protective and the other one is more supportive.
Third, there's such a bitter sweetness between them. Let me explain. When Kazemaru/Nathan is away, Endou/Mark is so fucking lost. He doesn't know what to do, he sinks into depression. He can't live without him. We all remember that 45th episode... And the Dark Emperors team... Yeah.. fucking sad. Also, without the captain, Kazemaru/Nathan can go completely crazy, for example... Becoming a villain? Acquiring more power to become stronger and prove to his friend that he reached his requirement level? I think that this boy just wanted his captain to be proud of him. Or he wanted to be as strong as him.
Fourth, their dominant colors are opposite but it shows how they can complete each other in a way. Endou/Mark's color is orange while Kazemaru/Nathan's is blue. A hot one and a cold one. The captain is really energetic and loud, while the defender is more calm and soothing.
Fifth, can we mention the English dub of the 65th episode? Endou/Mark calls Kazemaru/Nathan "pretty boy"? I'll never get over it, fellas. They love each other, your Honor!
I can definitely see Endou/Mark loving Kazemaru/Nathan in a very sweet way, always cheering him up, searching some physical contact from him like hugs or kisses, searching him with his eager eyes. On the other hand, the defender would learn to open up more to his boyfriend, go like "I'm worthy of his feelings, he chose me, so I have to become better everyday" and be more vulnerable.
Thanks for reading! Feel free to add something!