I'm not Rumiko Takahashi so I don't own Urusei Yatsura.

The first thing that Ataru noticed was an awful, pounding headache, the worst one that he had ever had. Despite all the direct head injuries he had acquired in the past year alone, this one was definitely the most painful, or at least in the top three. It felt like he had a C-clamp on his temples.

Ataru sat up with his head in his hands and groaned, trying in vain to relieve or tolerate the pain. It took about seven minutes for it to weaken thanks to his remarkable ability to recover quickly from anything. When he opened his eyes the morning light hurt his eyes, and it took another three minutes until he could see where he was.

What he saw surprised him. Ataru wasn't in his room, but Lum's spaceship. It also looked a little messy, but that was because some clothes were strewn all over the place. Then he noticed that they were his and Lum's clothes, including her trademark tiger skin bikini, and they looked like they were tossed carelessly as if torn off in a hurry.

"What the hell?" Ataru asked himself. He then looked down and saw he was completely naked with just a tiger-striped blanket for cover on a tiger rug. He was even more shocked to see an equally nude Lum under the blanket with him, still sleeping and looking at peace.

Ataru almost completely panicked. Did Lum and him really do... what it looks like they did? He tried to remember, but everything about last night was a complete blur. He could remember he and the oni leaving the Moroboshi house together to go somewhere, but nothing after that. What could have possibly led to the two of them doing this? And resulting in him not remembering any of it?

'Great. Now Lum's going to be pushing for marriage and commitment even more now.' Ataru semibitterly thought.

Lum started to shiver a little, and Ataru moved the blanket to cover her more. But she started to wake up, and quickly grabbed her own head. "Augh. Who hit me with a truck?"

"You've got a headache too?" He asked. His own was still there, but not as strong now.

"Yeah. And a pretty bad one too." Lum sat up holding her head, and the blanket fell off her, revealing her beautiful figure. Even with a headache, Ataru was too much of a lech to bother to cover her up again. Besides, however much of a nuisance the alien girl was, Ataru never said he didn't find her attractive. Virtually every man in Tomobiki thought that.

Lum eventually got well enough to notice her surrounding. Like her self-proclaimed 'husband' she wondered why they were in her UFO and they were naked. She then noticed her state of dress in front of the teenage boy, but felt no embarrassment. Why would she, considering what she had always wanted to do with him? "Darling, what happened last night?"

"I... don't remember. You don't either?" Ataru replied. Unlike her, he continued to keep his privates covered.

Lum shook her head. "Nope. I can remember being at Shutaro's party, but then... nothing."

Ataru then gasped and hit his hand with his fist. "That's right. We went to Mendo's party last night. The one to celebrate the end of summer and the start of our senior year. But I can't remember what happened when we were there."

Lum then coyly grinned. "Well, whatever it was, I'm glad it happened since we've clearly made love. I'm so happy."

Atari looked down. "I'm a little upset."

Lum did not like hearing this. "What?"

Ataru then acted quickly before she zapped him. "Lum, it was our first time for both of us, and neither of us can remember it. The first time is supposed to be special and something to remember forever. I feel we've been cheated if we can't remember it."

Lum blinked a couple of times. "You're right Darling. I wanted our first time to be like that too."

"I wonder what happened at Mendo's place that would make us want to do... that and then forget it. And give us both monster headaches as well." Ataru commented with a groan as his head kept throbbing.

"Let's go to his place and ask if he knows." Lum offered. Then she wrapped her arms around the boy's neck. "But first, why don't we have a time we can remember?"

Ataru gulped. "What, Lum?" He tried to think of a reasonable denial. But the feeling of her bare breasts pressed into his bare chest and the thought of last night's activities made nothing come to mind.

Lum giggled a little. Her loved one may be a pervert, but he wasn't as forceful as most would have you believe. He had never actually pressured any girl to actually sleep with him. Sure, his methods on asking a girl out needed improvement, but once he actually got a girl he was polite and patient. His initial reluctance was predicted and understandable to her. "Why not? Haven't you always wanted this with a girl? At least I'm going to let you." She then kissed him.

Coherent thought was beginning to leave Ataru's mind altogether. Lum just felt so good right then and there it was almost impossible for someone with even a small libido to resist her request. And for someone with a libido like Ataru's, it was nothing short of amazing that he wasn't already pushing her down and ravishing her. Then Lum used her tongue and rubbed his back, and Ataru's resistance vanished completely. This was a time they would definitely never forget, their second 'first' time.