To expand on a point from this post:
Dick Grayson is THE ALPHA you go to when you want sterotypical alpha affection. Like- he also does normal affection, obvi, but sometimes there's just this hyper-specific affection type that you crave deep in your bones and that is his NEICHE okay? Even if he wasn't an alpha, HES the person you go to for Alpha Affection^(TM)
There are non-alpha people who have that affection style too, but again it's like this HYPER-SPECIFIC affection type that's pretty rare for a person to just... naturally do without prompting or someone showing them its a possible;
think like our (non aob world) concepts of biting, laying your entire bodyweight on top of someone, cuteness agression- thats not something you introduce into a platonic relationship unless you're comfortable with someone because they aren't "normal" ways of epressing affection.
Dick Grayson is the person to go to if you want:
To be hand fed (bringing you food and shovinging it into your face until you eat)
Through scenting + scent marking the entire room you're in until you feel safe enough to relax
Hand on the back of your neck in public
A swaddling so tight you literally cannot move, even if he lets go of your blanket burrito
Him to growl and flash his teeth at you until the dynamic in the back of your head finally settles the FUCK down from the stress spiral that it's pulling you into (has done it to B for at least half an hour straight before, notching up when the the panic spikes again and softening when the panic starts to receed)
Dick gets Alpha-ish on Tim all the time. Sometimes even unprompted. Just usually in short bursts or in reaction to something.
So like- Dick's not acting that different from any other time that someone needs doting alpha brother- it's not even that dialed up either, it's just that it LASTS for a LONG time.
And also the fact that he's NEVER had a rut partner before. Like- he gets TERRITORIAL territorial. He's letting Tim in HIS space and that means that His Alpha decided that Tim is HIS the same way everything in HIS SPACE is. And that ... could be platonic.
Dick certainly acts like it is, that it's just him being 'Protective Of His Baby Brother. His Robin.' ^(TM) Denial is not just a river in egypt.
But then their ruts start syncing up. Which again, COULD be totally platonic, pack bonding. But... Then Dick goes HUNTING for Tim when he goes into Pre and Tim's in Gotham. Oracle CALLS Tim to come to Blüd and wrangle him.
Plausible denyability is streching thin. But of course they're closer than normal brothers. They've been through hell and back together. It's not entirely unpluasible that they imprinted onto each other. Dick is good at being reasonable like that.
They're Dick and Tim. Ofcourse they're weird about each other. Of course they take the opertunity to smother and bother each other. This behavior doesn't even raise any eyebrows from their friends and family.
Doesn't stop Tim from wanting, though.