Companionable, a.
Fitted to be a companion; fit for good fellowship; agreeable; sociable. "Each companionable guest." Mallett. "Companionable wit." Clarendon. -- Com*pan"ion*a*ble*ness, n. -- Com*pan"ion*a*bly, adv.
Shades of meaning
Fernald has no entry of its own for companionable; he lists it under friendly.
Where he writes about it:
Companionable and sociable refer to manner and behavior, cordial and genial express genuine kindliness of heart. — from friendly