unticklish

he's notoriously unticklish, even when you try your hardest.

my brother is completely unticklish; it's quite strange.

despite our attempts, the baby remained stubbornly unticklish.

she claims to be unticklish, but i'll test that theory.

he's an unticklish person, rarely showing any amusement.

it's unusual to find someone so completely unticklish.

the toddler proved to be remarkably unticklish during playtime.

being unticklish doesn't mean he's unhappy, just unresponsive.

we tried tickling him, but he was utterly unticklish.

she's an unticklish individual, preferring serious conversation.

despite our silly antics, he remained resolutely unticklish.