“Joohyun unnie?”

Wendy was sitting on her bed with her MacBook on her lap, dressed with an oversize long white tee. She looked at Irene, with her soft eyes behind the clear round specs sitting on the bridge of her nose. Her hair was tied up into a messy bun, the night lamp on the desk beside her illuminated on her bare face that was usually covered with stage makeups (Irene sometimes think that it made the younger seemed fiercer than the bundle of warmth she actually was). 

“I knocked, but I guess you didn’t hear it,” Irene said, head still peeking through Wendy’s bedroom door, “Are you busy?” She kept her hand on the door handle, in case Wendy would reject her this time around. 

It seemed that Wendy caught Irene’s pleading eyes. “No, I was just browsing through the net,” she closed her MacBook, “It was not important.” She stood up from her bed and walked towards Irene.

“Can we stay here instead, tonight?” Irene said, almost a whisper but clear enough for the younger to catch it. “My room smelled too much like fabric conditioner and right now I can’t…” Irene stopped; she did not know how to continue her words. However, Wendy never asked for an explanation or reason from her. The younger just hold her hand, pulling her inside then closing the door behind them. She then took both of Irene’s hands and gently drawing her to bed. 

Irene let herself be tugged to Wendy’s bed. She kept her gaze on their intertwined hand, on how their fingers filled each other’s empty spaces. 

“I am going to make you a cup of hot chocolate,” Wendy smiled, after she finished getting Irene in the blanket, “It will make you fall asleep easier.” Irene, however, did not let go of her hold of Wendy’s hand. “Joohyun unnie-“

“Stay, please?” Irene pleaded. She sounded broken. 

Wendy stilled. 

This is it. She asked for too much, Irene thought. 

“Okay.”

Wendy sat on the bed. “Scoot over,” she said as she went under the blanket, lying beside the older. Wendy then put her arm under Irene’s, tugging the later’s shoulder so that her head would rest on Wendy’s shoulder. “My bed is smaller than yours,” Wendy chuckled softly above Irene’s head, “You don’t want me to fall, right?”

They stayed silent for a while, but it was far from quiet. Leaning on Wendy’s shoulder, Irene could hear the younger’s heartbeat steadily. She could feel the younger’s chest rising and falling with each breath she took. Irene moved her arm, moving them across Wendy’s stomach before stopping at the later’s waist, holding her tight.

It felt right. She felt safe like this was where she belonged. The thought scared her. What if she didn't want to let go? What if tomorrow morning she woke up and somehow Wendy decided that they shouldn’t be doing this anymore? What if afterwards, she would spend the rest of her life searching for something remotely close but ended up empty-handed? What if everything ended before she got it all figured out? 

“Do you know,” Wendy muttered above her head, “What I was looking at before you came?” She didn’t wait for Irene’s answer before continuing, “I was watching videos about fascinating things in this world. You know that I like those, right?” 

Wendy chuckled. “Apparently there’s a thing called dark matter. Have you heard about it, unnie?” Irene shook her head, muttering a soft no against the younger’s neck. “I don’t know if you learned about it here, but they talked about it very briefly in the physic class I took back in Canada.”

Wendy laughed at Irene’s small groan. “Yes, I know you hate physics, unnie. You even mentioned it at a broadcast. I’ll just talk about it for a bit, okay? Just think of it as a bedtime story. I bet you’ll fall asleep quicker with this.”

“So, there was this astronomer that compare the mass of a cluster of galaxies by adding all the mass of stars, planets and the things in there with the mass he got went he derived from the velocities.” The younger lifted her head to look at Irene only to find the older was looking at her with furrowed eyebrows and confused stare. “Well, to simplify, he compared the mass of the galaxies he got when adding them like simple arithmetic to what he got while using a physical formula we usually apply when we are talking about gravities. What was interesting was that he found out that the two masses was nothing similar at all. The mass he got from deriving the formula was much much larger than the other one.”

“That was when he realised that there was something out there, something here that we can’t see. Something that doesn’t absorb light, like planets, or you, and me. Or bunnies.” Wendy chuckled, drawing small soothing circles on Joohyun’s shoulder, “Something that also doesn’t emit light like the stars. Something that behaves in a way that we can not understand, differently than what we know so far. Something dark, hence the name.” 

“What was even more fascinating is that now we found out that this world we lived in consist of five times more of dark matter than the normal matter we understand, and the both of them only added up to thirty per cent to what accounts to the universe. This suggests that everything that we know and everything we would possibly experience probably is only a very tiny fraction of reality.”

“And, this matter that we know very little of and cannot understand is actually what keeps the universe together. Without dark matter, there will not be enough gravity force to gather all the stars and form galaxies. The world we live in right now wouldn’t exist.” Wendy concluded, smiling as the thoughts fascinated her. 

“Isn’t it funny how the universe is thirteen billion years old, yet it still doesn't understand what's stopping it from falling apart?” Wendy murmured slowly, pulling Irene closer into her embrace. “They are just like us, still figuring things out.”

Irene nuzzled her head unto Wendy’s neck, tightening her hug towards the younger. It’s all right if she didn’t understand what was it that Wendy had that keeping her intact. She just needed to know that it was there, that it was real.

“Are you sleepy now, unnie? Is the bedtime story working?” Wendy whispered. The older could hear the smile from her voice. 

Irene hummed. “I still don’t get physics.” 

Wendy laughed softly. “Well, you’re not the only one.” She rested her chin on Irene's head, hand resting on the older's back. “Goodnight unnie.”

“Goodnight Seungwan.”