I feel like Keith and Lance are both ND but in different ways. Keith is the kind of guy who would really like physical contact and words of affirmation as love languages. He's pretty good at telling Lance how he feels about him later in the series. He'd probably appreciate the lack of ambiguity and take things at face value/put trust in I love yous.

Meanwhile Lance grew up in a big family so they might not have had as much money. Receiving gifts was a really big deal for him growing up. I can imagine Keith giving Lance a cool blue shell he found at an alien market and being all confused, thinking Lance doesn't like it when he goes still. Like he wants to take it back and is disappointed that Lance doesn't like it. But he does, he's just a bit overwhelmed by the gesture. Trying to show why he thought getting some silly shell was a good idea, Keith meekly tells him to look at this pretty part of it, turning it over in Lance's hands, pointing out an opalescent part that's all different kinds of blues. Says it reminds him of Lance's eyes.

Lance says something like "How would you know what colour my eyes are" because eye contact is not Keith's forte, but there's no bite behind it, and Keith doesn't get the joke anyway, just looks nervous. Keith just says they're pretty, as if he couldn't not have noticed. Lance puts it down on his side table gently. Keith says "You don't like it?" Lance gives him a super tender kiss. They kiss for a while holding each other, and Keith hugs him, sighing with contentment into lance's shoulder. Says "Holding you feels like home" then Lance dies on the spot