Quick headcanon

This can apply to most continuities, but especially to TFA…

But please imagine Decepticons– who loathe the idea of being perceived as warm-and-fuzzy like an Autobot– finding another way to expression devotion or affection.

Swearing undying loyalty, sharing what little there is in resources… these things are obvious in their intentions. ‘I will stand with you on the battlefield’ and ‘I will support you’... demonstrating a rare, but genuine interest in another’s well-being.

But when they really want to lay it on thick? They do something even rarer…

They pledge to mourn them, openly, should they fall.

While to an Autobot it may seem macabre, this means a great deal to Decepticons– who, as a reminder, are often made up of (former) “undesirable” and “disposable” castes. In their old life, no one would care if they lived or died. In their current life, the realities of war are harsh, and so you cannot afford to care for every single fellow soldier, when you know any day may be their last.

Deep feelings are seen as a vulnerability, as a weakness…

But when a Decepticon pledges to mourn you, they are saying they will willingly be vulnerable– if only for a moment– just for you.