Given the combination of the amount of time he spends with her, his sleeping position on the floor by her bed, his affection towards her and his general perversion, there was next to no chance he could mistake the legs of his master Louise. He could hardly believe his eyes, she was absolutely massive. He would be curious as to how he got this way, but the only possible conclusion was something different happening when she blew him up. It took a few moments, but he finally accepted the situation and stared up at her still figure.
Since he was unconscious, he had no way of telling what time it currently was, but she was here so it was at least long enough for her to cool down. Though her face was barely visible, he could still make out a slight glare, and her cheeks were slightly red, likely from leftover anger from earlier. She was looking around the room, likely looking for her perverted familiar, but with him nowhere in site he could hear a frustrated sigh and saw her lift her leg, only to stomp it on the ground. It wouldn't have been a very harsh stomp under normal circumstances, but with his size, Saito was knocked on his bottom.
He rubbed his head and began to stand up again, but when he looked up again, he noticed her underwear under her skirt, which made him lose focus as he crawled a bit closer. He was, however, broken from his trance when he realized why he could suddenly see them. She had lifted her leg, and began to remove her shoe, which she tossed in his direction. Luckily it missed him, if only by a small margin, and he had a similar experience with the second one.
It was without a doubt because she thought he wasn't here, but she began to strip from her clothing, presumably to change. He also had no doubt that she was probably expecting him to clean everything up when he 'returned'. He however, was not above averting his eyes, and instead decided to welcome the visual feast, until she stopped at her undergarments, and began walking in his direction towards the bed.
He knew he wouldn't get stepped on, due to how close he was to her shoes, but the sight of her giant form still shook him up a bit. It was also at this point that he realized that he probably needed to figure out what to do. He had the choices of either finding a way to climb her, be it catching her bare swinging foot as she walks by or getting her attention once she gets to the bed. He could also find a way to grab her attention from somewhere down here, without contacting her body. What to do...