You and L had been dealing with Kira's case for a while, you helped him a lot, and he silently acknowledged it, and was grateful for it. However, without realizing it, that skill with which you formulated strategies and assumptions, your firmness, accompanied by your sweetness and humor, inevitably attracted L. He didn't know why, he had never experienced anything like this, so at first he didn't acknowledge his feelings.
As the days passed, L found himself unconsciously doing romantic interactive actions (without knowing it), as he sought out your contact and warmth whenever he allowed himself to. He was confused and a little annoyed, he didn't want to take the next step, he didn't want to affect Kira's case with a possible relationship with you, because as much as you attracted him, justice came first for him.
One night, you and L had stayed late to work, both of you were a little tired, but in you, this was more prominent. L noticed your drowsiness out of the corner of his eye, his eyes moving stealthily but gently down your arm, until they reached your hand, as if he were caressing you telepathically. Then he reached out his hand, placed it close to yours, and as if by some small accident, he intertwined one of his fingers with yours, speaking in a low, soft voice.
"What do you think about what you are working on..."