We present simple models of N = 4 supersymmetric mechanics with ordinary and mirror linear (4, 4, 0) multiplets that give a transparent description of HKT, CKT, and OKT geometries. These models are treated in the N = 4 and N =2 superfield approaches, as well as in the component approach. Our study makes manifest that the CKT and OKT supersymmetric sigma models are distinguished from the more simple HKT models by the presence of extra holomorphic torsions in the supercharges. ⋆ On leave of absence from V.N. Karazin Kharkov National University, Ukraine 1 We follow the notation of [7] such that the numerals count the numbers of the physical bosonic, physical fermionic and auxiliary bosonic fields.2 N counts the number of real supercharges.1 [14,15,8] that complex sigma models admit an extended N = 4 supersymmetry for a geometry more general than HKT. This geometry with certain relaxed (compared to HKT) conditions for complex structures has been termed CKT in [8]. For some special CKT metrics (the so called OKT metrics), the models enjoying extended N = 8 supersymmetry can be written. Before explaining (we will do it shortly) what exactly HKT, CKT and OKT mean, let us say a few words about terminology. The abbreviation HKT stands for the Hyper-Kähler with Torsions geometry. It is worth mentioning that, generically, the HKT manifolds are not hyper-Kähler and not even Kähler. Their characteristic feature is the presence of three complex structures which form a quaternion algebra and are covariantly constant with respect to the appropriate connection with torsion. Likewise, CKT means Clifford Kähler with Torsions. This geometry is characterized by three complex structures which form the Clifford algebra but, in general, not the quaternion one. Finally, OKT (Octonionic Kähler with Torsions) manifolds are the manifolds of a dimension which is an integer multiple of 8, such that their geometry involves seven different complex structures forming the 7D Clifford algebra. These structures reveal some relation to the octonion algebra, though do not satisfy it. Neither CKT nor OKT manifolds are Kähler. Despite this mismatch (and the similar one for the generic HKT manifolds), we will follow the established literature tradition and use the names HKT, CKT and OKT for the considered type of geometries.The HKT geometry introduced in [14,15] is by now well understood by mathematicians [17]. This could not be really said, however, about the CKT and OKT geometries. One of the aims of our paper is to treat in detail some simple particular examples of the CKT and OKT manifolds to make more transparent their mathematical structure.