Dr. Vincent Asimov Nightshade was not used to expressing his feelings... Well, feelings such as these—love and affection. He was a cold man, often seen as rude and maybe a bit unfeeling. Most people saw him as cruel, mad, and very much insane. But you knew he was far from mad. In modern times, at least, he was mentally sound.
Vincent feels awkward around your aunt. Your aunt was certainly surprised to find out that you had fallen for a fictional character she had help you while she was gone. She was even more surprised that it was one of the loners, especially the ill-mannered scientist. "Are you sure about this?" she had asked upon her return, pulling you behind the bookstore counter.
Despite this, she was happy for you. Though she made sure to remind Vincent to take good care of you and not to bury himself in work. When walking into the bathroom (which had since become Vincent's laboratory), you're met with loud cackling. "I did it! I've developed a new strain of apples," he said proudly, holding up the apple for you to see.