Madara can go in for a kiss at any point in time if he likes someone that much. Initially when he first starts gaining feelings, he’ll be a little hesitant, mostly because he wants to inspect them and make certain that a kiss won’t completely ruin his chances. But Madara’s extremely forward, and not likely to wait long. When he wants something, he goes for it. It’s unlikely he’d wait until they actually became his s/o to kiss them. He’s too impatient and would have gone in for a kiss much earlier. It’ll probably be a random kiss, when he can’t hold back any longer. He knows he’s audacious and moves a little too fast, so if they back away or tense up when he leans in, he’ll wait a moment and see how they react. Do they want him to continue? Do they want him to stop? If it’s the latter, then he’ll at least be content knowing he tried, even if a little frustrated. But they should make up their mind as soon as possible, because if their reaction is delayed and they give him no feedback, he’s gonna go in to kiss them anyway. He doesn’t have time to sit and wait for them to decide

Tobirama on the other hand is extremely unlikely to go in for the first kiss. He’s way too paranoid and apprehensive, and too stubborn. I can see him having gone without kissing someone he liked, and waiting until they were actually a couple. He’s just that hesitant to make a move. His s/o will probably have to initiate it and even then, he’s really tense and easily flustered. Now this is all circumstantial, because let’s say Tobirama’s been having this tense, conflicting relationship with someone he likes, and the tension (sexual or not) is high. Then I can see him initiating a kiss in the heat of the moment, just pulling them in by the nape of their neck or curling a hand in their hair. During an argument specifically, even if it’s just a little one. It all comes out and he just goes for it without really thinking, which he regrets afterward, even if they react well. He’ll kiss them hard then pull back and wait in anxious apprehension. It’s probably only if they lean in for more that he’ll oblige and continue