Marinette laid on her stomach between Adrien's legs, propped up on his stomach via his elbow, with her sketchbook also there, sketching a design for some other event that Adrien couldn't keep up with (with her having been near the finish of university, there were just so many).
They were both listening to music, both earbuds in, at full blast, so they didn't hear the door open or even see Gabriel, which was a rare occurence in Adrien's bedroom.
Gabriel noticed them in a rather compromising postition (in his eyes). He shook his head and cleared his throat. When Marinette looked up a little bit, she noticed him, then screamed and moved.
Adrien jumped up as well.
"I'm sorry to interrupt...whatever you were doing, I just-"
Commence operation don't get killed!
"We're just friends!" The two exclaimed.
Gabriel groaned.
Every single time he caught them in a rather cute yet compromising (was that the trend these days?) position, they always said they were friends. Gabriel knew his son was better than to act around girl friends like he did with Marinette.
"What?" Adrien squeaked.
"Adrien, Marinette, if I hear those words again then I will die."
Gabriel heard Marinette mutter, surprised.
The couple watched Adrien's father leave the room.
"Looks like your father approves, I suppose..." She muttered.
"Agreed." He replied. "But we'd better not pull it again. Father doesn't joke."
"There's a difference between joking and exaggeration." Marinette told him. "Like...I'll keel over if we don't resume cuddling."
Adrien laughed and brought her back into his hold.
"Your boyfriend comes with death protection." He told her cheesily.
"Then I'm all for him." She kissed him, then moved her sketchbook away and fell asleep in his arms.
This was a request from Cinder95 to clarify. Go check them out!