He would make her understand. It was that simple. He couldn't wait for her to do it by herself; it might be too late then. And maybe she thought he wasn't serious, but he hadn't been more so in his entire life when he had said he couldn't live without her.
Gendo quashed any doubts in his mind as he rode the train. She wouldn't refuse. To think otherwise was... It weakened his resolve, and that would not do. This was not something he could be weak or wishy-washy for.
He had to be confident in his decision, his words forceful and direct so she would know he was serious. If he had doubts, Yui wouldn't have confidence in him. There could be no doubts, no going back. This was the right decision.
Yui would accept. She would understand.
"Yui."
She turned at the sound of his voice. There was something different about it. It was... deeper, more commanding. "Is there something wrong?" That was the only reason she could imagine he'd speak to her with that tone.
"No problem. I just need to tell you something." He stood there, sunlight reflecting off his glasses and hiding his eyes.
His eyes. That had always been one way she could read his mood without fail. "What is it?"
"Not here." Gendo beckoned her into the living room.
She followed him, very confused about what he wanted. He had never acted so... weird. "What is it?" she repeated.
When she was standing where he wanted her, back to the window, early afternoon sun shining behind her, Gendo struck. It was easier since he couldn't see her face that well.
Reaching into his pocket, he removed the box and held it out to Yui. "Yui," he began.
Her hand flew up to her mouth, and she stared at what he was holding. Eyes widened with surprise, they were locked on the box.
"Would you..." Gendo started to say.
Tentatively, Yui reached out and touched the box as if confirming its reality. It was certainly real, and this was all definitely happening.
Gendo's hand went over hers, brushing it delicately as he opened the box for her to see the contents.
It was small, but Yui wouldn't have expected much more really. She didn't need more. In fact, she didn't need a ring at all, but... "It's... it's..."
"An engagement ring. Will you marry me?"
Yui just stood there, her entire body frozen, unable to make a sound.
After a few moments of silence, Gendo spoke. "If you're not sure, you can..."
"Yes!" Suddenly her arms were around him and she was hugging him fiercely. "I will," she said, her face pressed into his shoulder.
With an inaudible sigh of relief, Gendo returned her hug, kissing her temple. "I bought this so you have to wear it though," he whispered, holding the box tightly.
"Of course," she answered hurriedly, releasing his neck. Yui wiped her eyes on her arm before looking back at the open box. She held out her hand, embarrassed at how badly it was shaking.
Gendo removed the ring and tossed the box to the side. Taking her hand to steady it, he slipped the ring on her finger. He smiled a little, liking the way the sun made it sparkle.
Yui turned and held her hand up, allowing the ring to catch direct sunlight. "It's... perfect."