Atk/def bond seal - best recipe ?

This seal is a beautiful reward for the next TT.
And i was wondering which unit would appreciate this skill ?

So a unit who needs an adjacent ally in his pref kit.
Amored units, Soren and Tana with their refined weapon...

And then i was thinking of Sharena and A.tiki.

Sharena has spd/def bond in her refined weapon. With Atk/spd bond in her A slot and Atk/def bond on the seal slot, does it stacks for a whopping +10 in atk def and spd ? Seems ok for arena when you don't have another bonus unit.

And A.Tiki. She's a great wall with her refined breathe. Atk/def boost if a sword or another dragon is in 2 spaces range. Soooo +15 in atk and def (atk/def bond in A slot and Seal) may be a thing ? Does it work ?